WO2007108212A1 - Periodic structure and method for manufacturing periodic structure and application product - Google Patents

Abstract

[PROBLEMS] To provide a periodic structure for achieving a propagation form of light which has been difficult or impossible to achieve conventionally. [MEANS FOR SOLVING PROBLEMS] The periodic structure having a refractive index or permittivity periodically varied includes an arbitrary axis orthogonal to a plane including the first and second PTVs out of first through third PTVs constituting a basic unit lattice, characterized in that the distribution of permittivity or refractive index in the unit structure and/or the basic unit lattice are mirror-asymmetric with respect to a plane parallel with the first PTV and/or a plane parallel with the second PTV.

Description

 Specification

 Periodic structure, method for producing periodic structure, and applied product

 Technical field

 TECHNICAL FIELD [0001] The present invention relates to a periodic structure having a period of about the optical wavelength and a method for manufacturing the same.

. The present invention also relates to a method for controlling propagation of electromagnetic waves, particularly light using the periodic structure, and applied products.

 Background art

 [0002] In recent years, a two-dimensional or three-dimensional periodic structure having a period of about the wavelength of an electromagnetic wave composed of two or more types of media called Photonic Crystal (hereinafter abbreviated as “P h C”). ) Is attracting attention as a means of controlling the propagation of electromagnetic waves.

[0003] The concept of the photonic band, which is the basis of P h C, was published by Non-Patent Document 1, and attracted attention since various interesting properties were presented.

[0004] Major structures, phenomena, analysis methods, and application examples that are already known are summarized on pages 78 to 137 of Non-Patent Document 2 and Non-Patent Document 3.

[0005] Non-Patent Document 4 and Non-Patent Document 5 explain the coupling between the anti-symmetric mode (odd symmetric mode) of self-cloning P h C (hereinafter abbreviated as “AC-PhC”) and external plane waves. Has been.

[0006] Patent Document 1: JP 2001-091701 A

 Patent Document 2: JP 2004-279713 A

 Patent Document 3: Japanese Patent Laid-Open No. 9-146064

 Patent Document 4: Japanese Patent Laid-Open No. 3-111806

 Patent Document 5: US Patent No. 3631288

 Patent Document 6: US Patent No. 5172267

[0007] Non-Patent Document 1: Ohtaka, PHYSICAL REVIEW B, Vol.19, No.10, pp.5057-5067,

15 May 1979

Non-Patent Document 2: Supervised by Akihiro Kawakami, "Photonic crystal technology and its applications" Shimushi Publishing Co., Ltd., 2002

 Non-patent document 3: FY2003 Patent Application Technology Trend Survey Optical Integrated Circuit, March 2004, Japan Patent Office

 Non-Patent Document 4: Hiroshi Honma et al., "Coupling of anti-symmetric modes and external plane waves in photonic crystals", 2004 Fall 65th JSAP Conference on Applied Physics, September 2004

 Non-Patent Document 5: Hiroshi Honma et al., "Optical attenuator using antisymmetric mode of photonic crystal", Society Conference of IEICE, September 2004

 Non-Patent Document 6: Takayuki Kawashima et al., "Fabrication of 2-D Photonic Crystal Polarization Separation Element and Its High Performance", IEICE Technical Committee on Optical Electronics, 0PE99-109

, December 1999

 Non-Patent Document 7: Edited by Yasuhiro Ayukawa, "Latest Solar Power Generation Technology and System", CMC Corporation, 2000

 Disclosure of the invention

 Problems to be solved by the invention

 In the situation described above, it is desired to provide a light propagation form, an element that realizes the propagation form, a method for manufacturing the element, and a use form of the element, which have been difficult in the past.

 [0009] When a plane wave is incident on an arbitrary position in the thin film optical element at an arbitrary incident angle (or a wide incident angle range), light is efficiently emitted in the plane of the optical element (in the thin film). It was impossible to propagate. For example, there is an example of coupling of an external plane wave using a diffraction grating, such as an optical waveguide Wood's Anomaly, but for any position in a thin film optical element, When plane waves are incident in a wide range of angles close to arbitrary, light does not propagate with high efficiency in the plane of the optical element (in the thin film).

 [0010] However, if such an optical element exists, the interaction between light and the medium constituting the thin film can be increased.

[001 1] Also, if two or more beams propagating in parallel to each other can be obtained from the same coherent light source, it is effective for optical recording and measurement using interference. However, it has been difficult with a conventional single optical element.

 The present invention has been made in view of the above circumstances, and provides a method for realizing a light propagation form that has been difficult or impossible in the past and an application thereof.

 Means for solving the problem

 [0013] The first invention is:

 A periodic structure consisting of two or more types of media whose refractive index is greater than 1.2. There is a combination in which the ratio of the refractive index between the contained media is greater than 1: 1.2, which constitutes the basic unit cell. Of the first to third basic translation vectors, including any axis perpendicular to the plane containing the first and second basic translation vectors, and a plane parallel to the first basic translation vector and Z Or the distribution of the dielectric constant or refractive index in the unit structure and the Z or basic unit scale are non-mirror symmetric with respect to the plane parallel to the second basic translational vector. A periodic structure whose dielectric constant changes periodically.

 [0014] The second invention is:

 There are periodic structures consisting of two or more types of media whose refractive index is greater than 1.2, and there are combinations in which the ratio of the refractive index between the contained media is greater than 1: 1.2. The first or second basic translation of the first to third basic translation vectors that make up the basic unit cell, where the refractive index or refractive index distribution and Z or the basic unit cell are non-rotationally symmetric and non-inverted symmetric Be non-mirror-symmetric with respect to a plane containing any axis orthogonal to the plane containing the vector and parallel to the first basic translation vector and to a plane parallel to the Z or second basic translation vector A periodic structure having a periodically changing refractive index or dielectric constant.

 [0015] The third invention provides

There are periodic structures consisting of two or more types of media whose refractive index is greater than 1.2, and there are combinations in which the ratio of the refractive index between the contained media is greater than 1: 1.2. A periodic structure in which refractive index or dielectric constant changes periodically, characterized in that the refractive index or refractive index distribution and the Z or basic unit cell have only translational symmetry. [0016] The fourth invention is:

 The periodic structure according to any one of the first to third inventions, characterized in that the second basic translation vector can have any length that is not zero.

[0017] The fifth invention provides

 The angle formed by the plane containing any two of the first to third basic translation vectors and the remaining one of the basic translation vectors is greater than 60 degrees <90 degrees The periodic structure described in any one of the first to fourth inventions.

[0018] The sixth invention provides

 The periodic structure is formed by laminating a plurality of thin films, the thin film layer has a periodic concavo-convex structure, and the convex portion in the concavo-convex structure is a convex portion having a plurality of distances from the top to the bottom. There is provided the periodic structure according to any one of the first to fifth inventions.

[0019] The seventh invention provides

 The length of at least one basic translation vector is from 100 nm to 100 nm, and at least one of the media included in the unit structure has a refractive index of 2 or more. The periodic structure according to any one of the first to sixth inventions.

[0020] The eighth invention provides

 Includes any axis orthogonal to the plane containing the first and second basic translation vectors, and parallel to the plane parallel to the first basic translation vector and Z or the second basic translation vector The periodic structure according to any one of the first to seventh inventions, wherein the electromagnetic field exhibits a non-mirror-symmetric eigenmode with respect to the surface.

[0021] The ninth invention provides

The electromagnetic field includes any axis perpendicular to the plane containing the first and second basic translation vectors, and is parallel to the plane parallel to the first basic translation vector and Z or the second basic translation vector. Non-mirror-symmetric with respect to the surface, non-rotationally symmetric with respect to the axis, exhibiting eigenmodes, characterized in that The periodic structure described in any one.

 [0022] The tenth aspect of the invention is:

 Regardless of the direction of excitation, the electromagnetic field includes any axis perpendicular to the plane containing the first and second basic translation vectors, and the plane parallel to the first basic translation vector and the Z or second Non-mirror symmetry with respect to a plane parallel to the basic translation vector, and having an eigenmode having no rotational symmetry three or more times with respect to the axis. The periodic structure according to any one of the seventh invention.

 [0023] The first invention is as follows:

 An electromagnetic wave beam incident at a predetermined angle on a surface including any two of the first to third basic translation vectors is propagated in a direction parallel to the surface, or the The periodic structure according to any one of the first to tenth aspects of the present invention, wherein the periodic structure and the air are propagated at an angle greater than a critical angle with respect to the surface.

 [0024] The first and second inventions are:

 The periodic structure according to any one of the first to eleventh aspects, wherein the incident beam is branched into a plurality of beams propagating in parallel to each other.

 [0025] The first invention is the

 The beam propagation direction described in the first invention or the beam branching direction described in the first invention is the direction of the first or second basic translation vector or the first to third basics. The periodic structure according to the first or first invention, characterized in that the direction is a projection of one basic translation vector remaining on a plane containing any two of the translation vectors. body.

 [0026] The 14th invention is as follows:

By changing the incident angle or incident position of the incident beam or the wavelength of the incident beam, the intensity ratio of the two beams propagating in the opposite directions in the plane of the first invention, or the same direction in the first invention The periodic structure according to any one of the first to thirteenth inventions, wherein at least one of the intensity ratio of the propagating beam and the branching interval changes. [0027] The fifteenth aspect of the invention is:

 Compared to the periodic structure described in any one of the first to seventh inventions, the cross-sectional area or volume of the basic unit lattice is the same, and one basic translation vector included in each is the same, and the unit The type and composition ratio of the medium in the structure are the same, and the center value of the energy corresponding to the wavelength of the antisymmetric mode of the periodic unit structure with mirror-symmetric basic unit cell and unit structure is ± 3 O o / A periodic structure having a periodically changing refractive index or dielectric constant, characterized by exhibiting the beam propagation form described in any of the first to fourth inventions at a wavelength corresponding to within o .

[0028] The 16th invention is

The features that you exist P n junction or pi _n junction in the medium of the unit within the structure of the periodic structure, the periodic structure described from the first to any of the first 5.

 [0029] The first seventeenth invention is:

 The periodic structure according to any one of the first to the sixteenth inventions, wherein the medium in the periodic structure contains a transparent conductor material, and the periodic structure has electrical conductivity. .

[0030] The eighteenth aspect of the invention is:

 The periodic structure according to any one of the first to seventeenth aspects, wherein the medium in the periodic structure contains a fluid and a solid.

[0031] The nineteenth invention is

 The periodic structure according to any one of the first to eighteenth inventions, wherein a part of the medium in the unit structure contains either a nonlinear optical material or a luminescent substance.

[0032] The 20th invention is

A periodic structure according to any one of the first to nineteenth aspects of the present invention, and another periodic structure connected to the periodic structure and having a continuous medium and the medium, wherein the periodic structure is The sum of the first to third basic translation vectors and the others A complex periodic structure characterized in that the sum of the first to third basic translation vectors constituting the periodic structure is different.

[0033] The second invention is

 A composite periodic structure comprising the periodic structure according to any one of the first to nineteenth aspects of the invention and a uniform medium connected to the periodic structure.

[0034] The second invention is as follows:

 A method of manufacturing a periodic structure in which at least one of anisotropic deposition and anisotropic etching is used on a substrate having an uneven shape formed with a one-dimensional periodicity or a two-dimensional periodicity. Because

 The average incident direction of deposited particles or etched particles to the substrate is not perpendicular to the substrate surface,

 The angle formed by the direction in which the incident direction is projected onto the substrate surface and the direction of the periodicity is in a range of 0 to 45 degrees,

 The method for producing a periodic structure according to any one of the first to seventh inventions.

[0035] The second invention is as follows:

 The periodic structure or composite periodic structure according to any one of the first to second inventions, a light source, a polarizer, a reflective polarization separation element, a walk-off polarization separation element, a reflection means, a phase plate, and diffraction A device comprising at least one selected from the group consisting of a grating, a scatterer, a spatial light modulator, an electrode, a photoreceptor, and a light receiver.

[0036] The 24th invention is as follows:

 A parallel beam source, a periodic structure according to any of the first to fourth inventions, and a reflective polarization separation element,

 A plane including any two of the first to third basic translation vectors in the periodic structure and the reflective polarization separation element are parallel to each other;

The device according to claim 1, wherein a beam from the parallel beam source is incident on the periodic structure a plurality of times by the reflective polarization separation element. [0037] The 25th invention includes

 A laser light source, a spatial light modulator, a lens, a photoconductor, and the periodic structure described in the first and second inventions,

 By the periodic structure, the beam incident from the laser light source is branched into a plurality of beams propagating in the same direction as the incident light and in parallel with each other,

 The spatial light modulator transmits or reflects at least one of the plurality of branched beams,

 The device, wherein the plurality of beams including at least a beam transmitted or reflected by the spatial light modulator are collected by the lens at the same location on the photoconductor.

 The invention's effect

 [0038] According to the most preferred embodiment of the present invention, it is possible to realize a light propagation state that could not be achieved conventionally. For example, when a plane wave is incident on an arbitrary position in a wide incident angle range, light can be propagated with high efficiency in the plane of the optical element. In addition, the incident beam can be split into two parallel beams having almost the same polarization state or three or more beams.

 Brief Description of Drawings

 FIG. 1 is a cross-sectional perspective view of a periodic structure as an example.

 FIG. 2 is a diagram showing a basic unit cell and a unit structure of the periodic structure shown in FIG. Fig. 2 (a) is a diagram showing the basic unit cell, and Fig. 2 (b) is a diagram showing the unit structure.

 [FIG. 3] FIG. 3 shows a basic unit cell and a unit structure of a periodic structure. Fig. 3 (a) shows the basic unit cell, and Fig. 3 (b) shows the unit structure.

 [FIG. 4] FIG. 4 is a band diagram in which the horizontal axis represents the wavelength of TE polarized light incident from the Z direction of the periodic structure having an infinite period formed by the basic unit cell shown in FIG.

 [FIG. 5] FIG. 5 is a band diagram in which the horizontal axis represents the wavelength of TE polarized light incident from the Z direction of the periodic structure having an infinite period by the basic unit cell shown in FIG.

[Fig. 6] Fig. 6 shows the ZX plane of a periodic structure with an infinite period using the basic unit cell shown in Fig. 3. It is a band diagram with the horizontal axis representing the wavelength of TE polarized light incident from a direction that is parallel to the surface and tilted 10 degrees from the Z axis.

 [FIG. 7] FIG. 7 is a band diagram with the horizontal axis representing the wavelength of the TM polarization incident from the Z direction of the infinite periodic structure having the basic unit cell shown in FIG.

 [FIG. 8] FIG. 8 is a band diagram with the horizontal axis representing the wavelength of the TM polarization incident from the Z direction of the infinite periodic structure having the basic unit cell shown in FIG.

 [Fig. 9] Fig. 9 shows the wavelength of the TM polarized wave incident from the direction tilted 10 degrees from the Z axis parallel to the ZX plane of the periodic structure with infinite period by the basic unit cell shown in Fig. 3. It is the band figure made into an axis.

 FIG. 10 is a diagram showing a self-cloning type two-dimensional photonic crystal and propagation of emitted light when a parallel beam is perpendicularly incident on the crystal. Fig. 10 (a) is a side view and Fig. 10 (b) is a front view.

 [FIG. 11] FIG. 11 is a diagram showing the propagation of outgoing light when a self-cloning type two-dimensional photonic crystal and a parallel beam are obliquely incident on the crystal with a small incident angle. Fig. 11 (a) is a side view and Fig. 11 (b) is a front view.

 FIG. 12 is a diagram showing a self-cloning type two-dimensional photonic crystal and propagation of emitted light when a parallel beam is perpendicularly incident on the crystal. Fig. 12 (a) is a front view and Fig. 12 (b) is a side view.

 FIG. 13 is a diagram showing a self-cloning type two-dimensional photonic crystal and propagation of emitted light when a parallel beam is incident on the crystal. FIG. 13 (a) is a front view, and FIG. 13 (b) is a side view.

 [FIG. 14] FIG. 14 is a model diagram in which the propagation of light between the “AC-2DPhC” 1001, the one-dimensional multilayer film 1003 and the air formed on the substrate 1002 shown in FIG. 10 is enlarged.

[FIG. 15] FIG. 15 is an enlarged model of the light propagation between “AC-2DPhC” 1401, the one-dimensional multilayer film 1403 and air formed on the substrate 1402 shown in FIG.

[Figure 16] Figure 16 shows the basic translation vector in self-cloning photonic crystals. FIG. 5 is a diagram showing a model of a unit structure in which a basic unit lattice in which all the tols are orthogonal and a medium distribution is biased. FIG. 16 (a) is a diagram showing a basic unit cell, and FIG. 16 (b) is a diagram showing a unit structure.

 FIG. 17 is a front view showing a substrate and the direction of deposited particles or etching particles incident on the substrate.

 FIG. 18 is a top view showing the substrate and the direction of the deposited particles or etching particles incident on the substrate.

 FIG. 19 is a top view showing the positional relationship between the target and the substrate.

FIG. 20 is a front view and a side view showing the positional relationship between the target and the substrate, and the incident direction of the deposited particles, etching particles, or etching particles. FIG. 20 (a) is a front view, and FIG. 20 (b) is a side view.

 FIG. 21 is a schematic perspective view showing the substrate 124 shown in FIG.

 FIG. 22 is a diagram showing the substrate 124 and the shaping layer 112 shown in FIG.

 [Figure 23] Figure 23 shows the actual 2D self-cloning photonic crystal (2

It is an electron micrograph of a cross section in the Z X plane of (D-collapse ACPC).

 FIG. 24 is a transmission characteristic graph. Figure 24 (a) shows the characteristics corresponding to the case where the incident beam is TE-polarized, and Figure 24 (b) shows the characteristics corresponding to the case where the incident beam is TM-polarized.

 [FIG. 25] FIG. 25 is a side view showing the basic structure of a hodara-frac recording apparatus.

 FIG. 26 is a side view showing the operation during recording.

 FIG. 27 is a side view showing an operation during reproduction.

 FIG. 28 is a view showing H B S used in Example 2.

 FIG. 29 is a diagram showing a polarization-compensating optical integrator and propagation of incoming and outgoing light.

 [FIG. 30] FIG. 30 is a schematic side view of a “2D-collapsed ACPCj-based photoelectric conversion device based on a-SiC and thin-film polycrystalline silicon.

 FIG. 31 shows the basic unit cell and unit structure of “2D-collapse ACPC” 3003 shown in FIG. Fig. 31 (a) shows the basic unit cell, and Fig. 31 (b) shows the unit structure.

[Fig.32] Fig. 32 shows three-dimensional photonics produced using Ti0 ₂ , Sn0 ₂ , and iodine solutions. It is sectional drawing of a crystal.

 Explanation of symbols

 [0040] 201 First P TV

 202 Second P TV

 1001 Self-cloning type 2D photonic crystal

 1004 Incident parallel beam

 1005 Output beam

 1006 Output beam

 1007 Output beam

 1008 Output beam

 1009 Output beam

 1010 Output beam

 3107 Area occupied by i-type polycrystalline silicon

 3108 Area occupied by i-type polycrystalline silicon

 3109 Area occupied by n-type polycrystalline silicon

 3110 Area occupied by p-type amorphous silicon carbide

 3111 Area occupied by p-type amorphous silicon carbide

 3112 Area occupied by p-type amorphous silicon carbide

 BEST MODE FOR CARRYING OUT THE INVENTION

[0041] 1. from 1 to 7

 Hereinafter, the first to seventh inventions will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional perspective view of a periodic structure and peripheral members as an example. A region 101 to a region 111 occupied by a medium having a refractive index n½1.5, and a region 113 to a region 123 occupied by a medium having a refractive index _n 4 shown by hatching form a periodic structure. Reference numeral 124 denotes a substrate, and reference numeral 112 denotes an intermediate layer (shaping layer) between the substrate and the periodic structure. The periodic structure shown in FIG. 1 is a kind of multilayer thin film, and the film thicknesses of the region 101 to the region 111 are each about 150 nm, and the film thicknesses of the region 113 to the region 123 are each about 100 nm. [0043] Fig. 2 shows the basic unit cell (prim is ive eel and abbreviated as Γ P r C) and unit structure (basis, abbreviated as "BAS") of the periodic structure shown in Fig. 1. FIG. Fig. 2 (a) is a diagram showing P r C. The first primitive translation vector (hereinafter abbreviated as Γρ τ Vj) 201 is 41 Onm in length and parallel to the X direction. The PT V202 is 251 nm long, has an angle of 86 degrees with respect to the XY plane, and is parallel to the ZX plane. The third P TV is parallel to the Y axis and the length is arbitrary (undefined). Here, indefinite length means that the distribution of the medium in the BAS is uniform in the Y direction, and that the length of the PTV cannot be defined uniquely (arbitrary). Reference numerals 203 to 206 denote lattice points. Fig. 2 (b) is a diagram showing BAS, which is a cross-sectional view in a plane parallel to the plane containing the first PT V201 containing the midpoint of the third PTV and the second PTV202. BAS consists of a region 207 occupied by a medium with n = 2.4, a region 208 occupied by a medium with n = 1.5, and a region 209 occupied by a medium with n = 1.5 in the visible light range. However, as a periodic structure, region 208 and region 209 are continuous, and BAS is essentially composed of two regions. Reference numerals 210, 211, and 212 are vertices of a region of the medium where n = 2.4 (and also vertices of a region occupied by the medium of n ½1.5). The periodic structure of PrC and BAS shown in Fig. 2 is a kind of two-dimensional self-cloning photonic crystal (hereinafter abbreviated as “AC-2DPhC”).

 [0044] The periodic structure by PrC and BAS shown in Fig. 2 or the periodic structure by PrC and BAS, which is an extension of PrC and BAS shown in Fig. 2 to a three-dimensional periodic structure, is described above. The first to seventh inventions will be described. Note that Pr C and BAS shown in Fig. 2 in which P r C and BAS are expanded to a three-dimensional periodic structure have the same cross-sectional view in the YZ plane as in Fig. 2 and the cross-sectional view in the XY plane as in Fig. P r C and BAS are the same.

 [0045] The first invention can be explained by P r C and BAS shown in FIG.

This is because the periodic structure by PrC and BAS shown in Fig. 2 selects PTV201 as the first PTV and PTV of indefinite length parallel to the Y axis as the second PTV. r The plane containing the first and second PTV in C (here, the XY plane) Is parallel to the second PTV (in this case, parallel to the YZ plane, where X is arbitrary). And any of the refractive index distributions in BAS cannot be mirrored, while containing any axis orthogonal to the plane containing the first and second P TVs in P r C, The plane parallel to the first PTV201 (here the plane parallel to the ZX plane, Y is arbitrary) is the plane containing the midpoint of the length of the second PTV, and the refractive index in PrC and BAS This is because it becomes a mirror surface for any of the distributions.

 [0046] The second invention can be explained by the periodic structure of PrC and BAS shown in FIG. This is because the refractive index distribution in BAS is non-rotational and non-inversion symmetric. P r C has two-fold rotational symmetry. Also, “The distribution of dielectric constant or refractive index in the unit structure and Z or basic unit cell is non-rotation symmetric, non-inversion symmetry” means that the unit can be rotated or inverted with respect to any axis or point. Either the distribution of dielectric constant and refractive index in the structure and the basic unit lattice are not the same as the original, or the distribution of either dielectric constant and refractive index in the unit structure or the basic unit lattice is the same as the original It means not to be.

 [0047] The third invention relates to an example in which the refractive index distribution in BAS in which PrC and BAS shown in Fig. 2 are expanded to a three-dimensional periodic structure has no symmetry except translation. it can. Since it is a periodic structure, it naturally has translational symmetry. The description for the refractive index also holds for the dielectric constant ε.

 [0048] The fourth invention can be explained by an example in which the second ΡΤ V can take any length that is not the opening in PrC and BAS shown in FIG. This is due to the fact that the distribution of the medium in B A S is uniform in the direction of the second P T V and has so-called continuous translational symmetry.

[0049] The fifth invention can be described with reference to FIG. This is because the angle between the plane containing the first and second PTV shown in Fig. 2 (a) (parallel to the XY plane) and the remaining third PT V is 86 degrees, greater than 60 degrees and 90 degrees This is because the surface including any two P TVs among the first to third P TVs remains and remains 1 The angle formed by two PTVs is preferably greater than 65 degrees and smaller than 85 degrees, more preferably greater than 75 degrees and less than 85 degrees. If it is larger than 65 degrees and smaller than 85 degrees, the electromagnetic waves incident on the surface of the periodic structure, which is a plane parallel to the plane including the first and third PTVs, in the eleventh invention to be described later, This is advantageous because it propagates with a larger ratio in the direction parallel to the plane containing the PTV. If the angle is greater than 75 degrees and smaller than 85 degrees, the manufacture according to the 22nd invention described later is easy, and the 11th invention described later is a plane parallel to the plane including the first and third PTVs. This is advantageous because electromagnetic waves incident on the surface of a periodic structure can propagate with a larger ratio in a direction parallel to the plane including the first and third PTVs.

 The sixth invention can be explained by a periodic structure formed by laminating thin films having a plurality of concavo-convex structures in the Z-axis direction as shown in FIG. In addition, it can be seen from FIG. 2 that the vertex 210 of the medium region of n = 2.4 corresponds to the uppermost portion of the convex portion, and the vertexes 211 and 212 correspond to the lowermost portion of the convex portion. Since the distance between the vertex 210 and the vertex 211 is different from the distance between the vertex 210 and the vertex 212, there are two types (plurality) of distances from the top to the bottom of the convex portion. This form is one of the simplest ways to break the symmetry of BAS. Further, as will be described later, there is the following relationship between the length of the first and third PTVs and the wavelength of the electromagnetic wave (light) indicating the propagation characterizing the eleventh or twelfth invention.

The wavelength of the electromagnetic wave (light) indicating the propagation characterizing the 11th or 12th invention is a value obtained by multiplying the first PTV by the refractive index of the medium having the largest refractive index contained in the BAS (for example, FIG. 1). In the periodic structure described, the wavelength is about 980 nm) or less, preferably a value obtained by multiplying the first PTV by the weighted average of the refractive index of the medium contained in the BAS (for example, the periodic structure shown in FIG. 1). In the body, the wavelength is about 760 nm or less, more preferably less than the value obtained by multiplying the first PTV by the weighted average of the refractive index of the medium contained in the BAS and included in the BAS for the third PTV. It is not more than the value obtained by multiplying the weighted average of the refractive index of the medium and not less than the first PTV (for example, in the periodic structure shown in FIG. 1, the wavelength is not less than 410 nm and not more than 465 nm). [0051] Regarding the seventh invention, as shown in FIG. 2, the first PTV is 410 nm, the second PTV is indefinite (optional), and the third PTV is about 251 nm. The 1st and 3rd PTVs meet the requirements of lengths from 100nm to 1m. The condition is also satisfied for the point that n = 2.4 of one of the included media. Note that the length of the PTV and the refractive index of the medium included are closely correlated with the wavelength of the corresponding electromagnetic wave.

 Regarding the length of the at least one PTV, the wavelength of the electromagnetic wave incident on the surface of the periodic structure, which is a plane parallel to the plane including the first and second PTVs in the first aspect of the invention described later, is In the ultraviolet region, the thickness is preferably 100 nm to 400 nm, more preferably 150 nm to 350 nm. Similarly, when the wavelength of the electromagnetic wave is in the visible light region, it is preferably 200 nm to 700 nm, more preferably 350 nm to 500 nm. Similarly, when the wavelength of the electromagnetic wave is in the near infrared region, it is preferably 300 nm to 1000 nm, more preferably 400 nm to 700 nm.

 [0052] It should be noted that P r C is defined by a general selection of P r C with the best symmetry, with the exception.

 [0053] 2. Words from 8 to 10

 Hereinafter, the eighth to tenth aspects of the invention will be described in detail with reference to the drawings.

 [0054] FIG. 3 is a kind of P r C and BAS of the periodic structure. Figure 3 (a) shows P r C. The length of the first PT V301 is 41 Onm, parallel to the X direction, and the length of the second PT V302 is 251 nm with respect to the Z axis. Parallel. The third P T V is parallel to the Y axis and the length is arbitrary (undefined). Indefinite length means that the distribution of the medium in BAS is uniform in the Y direction, and the length of PTV cannot be uniquely defined (optional). Reference numerals 303 to 306 are lattice points.

[0055] FIG. 3 (b) is a diagram showing the BAS, and is a cross-sectional view in a plane parallel to the plane including the first and second PTVs including the midpoint of the third PTV. BAS consists of a region 307 occupied by a medium with n = 2.4 in the range of visible light, a region 308 occupied by a medium with n = 1.5, and a region 309 occupied by a medium with n = 1.5. However, as a periodic structure, region 3 08 and region 309 are contiguous, and BAS consists essentially of two regions. The periodic structure of PrC and BAS shown in Fig. 10 is a kind of AC-2DPhC.

 [0056] P r C and BAS shown in Fig. 3 and P r C and BAS shown in Fig. 2 are the hexahedrons formed by P r C with the same first and third PTV lengths. The volume is the same. Moreover, the refractive index and the filling rate of all the contained media are the same. On the other hand, PrC and BAS shown in Fig. 3 are mirror-symmetric with respect to the plane including the axis perpendicular to the plane containing PT V301 and PT V302 and the midpoint of PT V301, and two rotational symmetry. And inversion symmetry.

 FIG. 4 is a band diagram in which the horizontal axis represents the wavelength of TE polarized light incident from the Z direction of the periodic structure with an infinite period due to PrC shown in FIG. A large point (thick line) represents the symmetric mode, and a small point (thin line) represents the anti-symmetric mode. The first band of the antisymmetric mode exists from the wavelength of about 680 nm to the wavelength of about 790 nm, the second band of the antisymmetric mode exists from the wavelength of about 440 nm to the wavelength of about 540 nm, and the third band of the antisymmetric mode is about the wavelength. Present below 430nm. The third band of antisymmetric mode overlaps with the band of even symmetric mode.

 FIG. 5 is a band diagram in which the horizontal axis represents the wavelength of the TE polarization incident from the Z direction of the periodic structure with an infinite period due to PrC shown in FIG. Fig. 6 is a band diagram with the horizontal axis representing the wavelength of TE polarized light incident from a direction tilted by 10 degrees from the Z axis and parallel to the ZX plane of the periodic structure with infinite period due to PrC shown in Fig. 3. is there.

 [0059] FIG. 6 is a band diagram in which the horizontal axis indicates the wavelength of the TM polarization incident from the Z direction of the periodic structure having an infinite period due to PrC shown in FIG. A large point (thick line) represents the symmetric mode, and a small point (thin line) represents the anti-symmetric mode. The first band of the antisymmetric mode exists from a wavelength of about 580 nm to a wavelength of about 720 nm, and the second band of the antisymmetric mode exists from a wavelength of about 400 nm to a wavelength of about 550 nm. The second band of antisymmetric mode almost overlaps with the band of even symmetric mode.

[0060] FIG. 7 is a band diagram in which the horizontal axis represents the wavelength of the TM polarized wave incident from the Z direction of the periodic structure having an infinite period due to PrC shown in FIG. Figure 8 shows the P r shown in Figure 3. It is a band diagram with the horizontal axis of the TM polarization wavelength incident from a direction parallel to the ZX plane of the periodic structure with an infinite period by c and tilted 10 degrees from the Z axis.

 [0061] The eighth invention can be explained by all the bands in the band diagrams shown in Figs. All bands in the band diagrams shown in Fig. 5 and Fig. 8 cannot distinguish between symmetric and antisymmetric modes. This includes any axis (axis parallel to the Z axis in FIG. 2) perpendicular to the plane where P r C and BAS already contain the first and second PTV (XY plane in FIG. 2), and the second Because it is non-mirror-symmetric with respect to a plane parallel to the PTV (parallel to the YZ plane), the eigenmode of the electromagnetic field is also non-mirror-symmetric with respect to the plane.

 [0062] The ninth invention can be explained by all the bands in the band diagrams shown in Figs. Similarly, P r C and BAS are in any direction perpendicular to the plane containing the first and second PTV (XY plane in Fig. 2) (axis parallel to the Z axis in Fig. 2). And because BAS is already non-rotation symmetric, the eigenmodes of the electromagnetic field are also non-rotation symmetric about the axis.

 [0063] The tenth invention can be explained by all the bands in the band diagrams shown in Figs. Similarly, P r C and BAS already include an arbitrary axis (axis parallel to the Z axis in FIG. 2) perpendicular to the plane containing the first and second PTVs (the XY plane in FIG. 2), and Since it is non-mirror symmetric with respect to the plane parallel to the second PTV (parallel to the YZ plane) and non-rotationally symmetric with respect to the axis, the eigenmode of the electromagnetic field is not affected by this plane regardless of the direction of excitation. On the other hand, it is non-mirrored and has no rotational symmetry of 3 or more times with respect to the axis.

 [0064] In the band diagrams shown in FIGS. 6 and 9, the symmetric mode and the antisymmetric mode cannot be distinguished, but the reason is described in Non-Patent Document 4 and Non-Patent Document 5.

[0065] The band diagram shown in Fig. 4 has an even symmetric mode (Even) band and an antisymmetric mode (Odd) band. In the band diagram shown in Fig. 5, the symmetric mode band and the antisymmetric mode band exist. Although no distinction can be made between the bands, the two band diagrams are almost identical in terms of the inclination of each band, the frequency of folding, the frequency where the band gap exists, etc. The Therefore, the band in Fig. 5 that corresponds to the band of antisymmetric mode in Fig. 4 is called the band of antisymmetric like mode. The band in Fig. 5 corresponding to the even symmetric mode band in Fig. 4 is also called the even symmetric like mode band.

 [0066] The fact that the even-symmetric mode and the anti-symmetric mode cannot be distinguished is similar to the case where the beam described in Non-Patent Document 4 is perpendicularly incident and obliquely incident. However, the difference between the band diagram of FIG. 5 compared to the band diagram of FIG. 4 and the band diagram of FIG. 6 compared to the band diagram of FIG. The even symmetric like mode band and the antisymmetric like mode band shown in Fig. 5 corresponding to the matching even symmetric mode and antisymmetric mode tend to deviate, and the even symmetric mode band shown in Fig. 5 is antisymmetric. Fig. 6 shows a significant deformation of the band structure, such as the generation of a band gap near the frequency where the mode band exists, but Fig. 5 does not show such a tendency.

 [0067] Further, the band edge where the antisymmetric like mode band exists with respect to the antisymmetric mode band has a frequency deviation of about 7%. If the angle between the plane containing the first P T V and the third P T V in Figure 2 and the second P T V is even smaller, the difference in frequency is even greater. For PrC and BAS similar to those in Fig. 2, a deviation of about ± 30% is possible.

 [0068] When comparing the TM polarization band diagrams shown in FIGS. 7 to 9, the TE polarization band diagrams shown in FIGS. 4 to 6 show almost the same tendency. Yes.

 [0069] 3. Description of the 1st to 15th inventions

 Hereinafter, the 11th to 15th inventions will be described in detail with reference to the drawings.

[0070] When the light having a specific wavelength (electromagnetic wave) is incident on the periodic structure (P h C) and the device including Z or the P h C according to the first to tenth inventions, the following (A) ~ (R) phenomenon occurs. [0071] (A) A part of the electromagnetic wave incident on the surface of the periodic structure that is parallel to the plane including the first and second PTVs passes through the first and second PTVs inside the periodic structure. Propagates in a direction parallel to the plane (corresponding to the eleventh invention).

 (B) Part of the electromagnetic wave incident on the surface of the periodic structure, which is a plane parallel to the plane including the first and second PTVs, becomes diffracted light inside the periodic structure. And Z or direction of the second P TV ”and Z or“ direction parallel to the plane containing the first and third P TV ”and Z or“ parallel to the plane containing the second and third P TV ” Propagating in the direction.

 (C) The diffracted light of (B) above is totally reflected at the interface between the periodic structure and the uniform medium, or is reflected except for a part, and the rest is transmitted. (Corresponds to the eleventh invention). In other words, the periodic structure also functions as a waveguide.

 [0072] (D) The diffracted light of (B) that has passed through the interface between the periodic structure and the uniform medium is reflected at the interface between the uniform medium and air (another uniform medium), and again the periodic structure. Incident on the body.

 (E) From (B) to (D) above, a plurality of beams traveling in the same traveling direction as the incident beam and in the same direction as the reflected beam can be obtained (beam splitting, corresponding to the twelfth invention). Further, the plurality of beams have substantially the same polarization state.

 [0073] (F) The light propagation direction in (A) and the light branching direction in (E) are: Γ direction of first P TV and vice versa, and Z or “second P TV Direction and its opposite direction ”or“ direction in which the third PTV is projected on the first and second PTV and its opposite direction ”(corresponding to the thirteenth invention).

 (G) The intensity ratio of the beam propagating in the same direction and the branch interval vary depending on the incident angle (corresponding to the fourteenth invention).

 (H) The intensity ratio of the beam propagating in the same direction varies depending on the incident position (corresponding to the 14th invention).

(I) The branching interval of the two beams propagating in the opposite directions in the plane at the same incident angle and incident position varies with the wavelength approximately in proportion to the wavelength. Also incident The intensity ratio of the branched light when the angle and the incident position are changed also changes (corresponding to the fourteenth invention).

 [0074] (J) The beam splitting interval depends on the size of the in-plane period, the refractive index and wavelength of the medium, the substrate material, and the thickness.

 (K) Except for the specific wavelength, the propagation direction of the beam follows normal geometric optics.

(L) The wavelengths indicating propagation described in (A) to (J) above are the same in the area or volume of P r C and BAS, the periodic structure, and P r C shown in Fig. 2, and each included. One PTV is the same, the type of medium in BAS, the composition ratio is the same, and it is in the vicinity of the wavelength where the antisymmetric mode of the periodic structure of P r C and BAS shown in Fig. 3 exists. (There is a deviation of 7% in frequency. In some cases, there is a deviation of 10%, a deviation of 15%, a deviation of 20%, and a deviation of 30O / O) (corresponding to the fifteenth invention) .

 (M) The product of the size of the first or third PTV and the largest refractive index among the contained media is larger than the longest wavelength at which propagation from (A) to (K) occurs.

 (N) The range in which a plurality of beams propagating in parallel to each other as described in (E) above appears is limited to the range of the multidimensional periodic structure. In addition to the multidimensional periodic structure, the multiple beams propagating parallel to each other described in (E) above are not generated.

 (O) The light propagating in (A) and (B) above leaks out from the part where the period is disturbed, such as defects and foreign matter on the surface.

 (P) Propagation of light from (A) to (J) above is not possible even if light of a wavelength with an antisymmetric mode is obliquely incident on the periodic structure of PrC and BAS shown in Fig. 3. Does not occur.

Hereinafter, the above-described behavior of light will be described in detail with reference to the drawings. FIG. 2 shows the result of investigating the propagation by entering a parallel beam with a selected polarization direction into the periodic structure of PrC and BAS shown in FIG. 2 formed on the substrate.

FIG. 10 shows a wavelength of 532 nm at the center of “AC-2DPhC” 1001 formed on the substrate. It is a figure which shows propagation | transmission of the emitted light when the parallel beam which has a Gaussian intensity distribution by the laser beam of normal incidence is carried out. Fig. 10 (a) is a side view and Fig. 10 (b) is a front view.

 [0077] AC-2DPhC 1001 is laminated on a 0.5-thick fused quartz substrate 1002, and is uniform (one period) in the Y-axis direction. At the same time, a one-dimensional (planar) multilayer film 1003 is also laminated on the substrate 1002. In the figure, reference numeral 1004 indicates an incident parallel beam, and reference numerals 1005 to 1014 indicate output beams. Similarly, reference numeral 1015 denotes “incident position and outgoing position of the incident parallel beam 1004 in AC-2DPhC 1001, and reference numerals 1016 and 1017 denote“ exit position of outgoing beam in AC-2DPhC 1001. Reference numeral 1018 denotes ΓΑ C-2DPhCj Defect region existing in 1001, reference numeral 1019 represents a scatterer applied to the surface layer of the one-dimensional multilayer film portion.

 First, as shown in FIG. 10, transmitted light in accordance with Snell's law and two beams in which the transmitted light and the traveling direction are parallel were confirmed. As for the light propagating to the reflection side, the reflected light in accordance with the law of reflection and the two beams whose traveling direction was parallel to the reflected light were confirmed. The beam emission position was limited to the range of the multidimensional periodic structure, and the interval between the three beams propagating in the same direction was the same at 2.0 mm.

 [0079] In addition, the same behavior was confirmed in all cases where T E, T M, and electric field oscillation directions were each linearly polarized waves inclined by 45 degrees with respect to T E polarized waves. Furthermore, it was confirmed that the output beams 1008, 1009, and 1010 have almost the same polarization state.

[0080] Next, when the incident position of the beam is near the end in the X direction of “AC-2DPhC” 1001, four beams are emitted only from the range where “AC-2DPhC” 1001 exists, and four The beam spacing was confirmed to be the same as in Fig. 10. It was also confirmed that the beam intensity ratio can be changed depending on the incident position, and in particular that the intensity of the output beam 1008 can be made larger than that of the output beam 1009.

[0081] In addition, there is light scattered by the roughness of the AC-2DPhC surface (defect region 1018), and the three outgoing beams on the end face of the one-dimensional multilayer film 1003 laminated simultaneously with the "AC-2DPhC" 1001 Output beam 101 1 to output beam from the position on the extended line where Since the beam 1014 was output as a beam, it was confirmed that light propagated in the thin film surface. Furthermore, when scatterer 1019 was applied to the surface layer of the one-dimensional multilayer film portion, light leakage from scatterer 1019 was also confirmed.

 [0082] Next, when the substrate 1002 and quartz plates of various thicknesses were connected so as to be optically integrated through refractive index matching oil, the distance between the output beams 1008 and 10009 changed.

 [0083] Fig. 1 1 shows "AC-2DPhC" 1001 formed on the substrate and a parallel beam having a Gaussian intensity distribution with a laser beam having a wavelength of 532 nm at the center of "AC-2DPhC" 1001. FIG. 5 is a diagram showing the propagation of outgoing light when the light beam is obliquely incident with a small incident angle. The incident surface is parallel to the Z X plane. Fig. 11 (a) is a side view and Fig. 11 (b) is a front view.

 In the figure, reference numeral 1101 denotes an incident parallel beam, and reference numerals 1102 to 1107 denote output beams. Similarly, reference numeral 1108 denotes the incident position and outgoing position of the incident parallel beam in “AC-2DPhC” 1001, and reference numerals 1 109 and 1 110 denote the outgoing position of the outgoing beam in “AC-2DPhC” 1001.

 [0085] In the example shown in Fig. 11, the branching interval of the light propagating to the transmission side changes with the incident angle to the maximum at the time of vertical incidence. The traveling direction of the beam propagating to the reflection side was the same as the direction indicated by the law of reflection in geometric optics. Furthermore, it was possible to change the intensity ratio of the beam propagating in the same direction by changing the incident angle on both the transmission side and the reflection side.

 [0086] Further, as compared with the case of FIG. 11, when the incident angle was increased, the number of beams propagating to the transmission side and the reflection side decreased to two. Furthermore, when the incident angle was increased, there was a case where the beam became one. When the incident direction was further changed (rotated around the X axis), the same beam splitting occurred, and the traveling direction of the beam propagating to the reflection side was the same as the direction indicated by the reflection law in geometric optics. Met. It was also confirmed that the ratio of transmitted light and reflected light can be changed by the incident angle.

[0087] Next, when the wavelength of the incident light was changed, even when a parallel laser beam with a wavelength of 473 nm was incident, the behavior similar to that at the wavelength of 532 nm in Fig. 10 was observed. did. However, when the wavelength was 473 nm, the beam separation interval at normal incidence was reduced to 1.4 mm. In addition, at a short wavelength of 405 nm, the beam separation interval at normal incidence was about 1.0 mm. Furthermore, at a wavelength of 650 nm, it was confirmed that the propagation of the incident parallel beam follows the usual Snell's law and the reflection law.

 As described above, the beam splitting interval at the same incident angle has a linear function relationship up to a predetermined wavelength. At 532 nm, the ratio of the beam that follows normal geometric optics to the branched light is smaller when TE polarized light is incident than when TM polarized light is incident (more branched light), and at 473 nm, the normal geometric optics is used. It was confirmed that the ratio of the beam following the beam to the branched light was larger (with less branched light) when the TE polarized light was incident than when the TM polarized light was incident. The branching itself occurs with both T E and T M polarizations, but the intensity of the branching light varies depending on the polarization, and the ratio of the beam and the branching light according to ordinary geometrical optics also depends on the wavelength. The angle formed between the output beam 101 1 and the output beam 1 013 also changed depending on the wavelength.

 [0089] Further, when a parallel laser beam having a beam diameter of 3 mm and a wavelength of 473 nm was incident, the branched beams overlapped to confirm an interference pattern.

 [0090] FIG. 12 shows a case where a parallel beam having a Gaussian intensity distribution by a laser beam having a wavelength of 532 nm is vertically incident on “AC-2DPhC” 1201 formed on a substrate 1202 and “AC-2DPhC” 1201. It is a figure which shows propagation of the emitted light. Fig. 12 (a) is a side view and Fig. 12 (b) is a front view.

 In the figure, reference numeral 1203 denotes a planar multilayer film in which the medium is continuous with “AC-2DPhC” 1201, reference numeral 1204 denotes an incident parallel beam, and reference numerals 1205 to 1215 denote output beams. Reference numeral 1216 indicates the incident position and exit position of the incident parallel beam in “AC-2DPhC” 1201, and reference numerals 1217 and 1218 indicate the exit position of the exit beam in “AC-2DPhC” 1201. “AC-2DPhC” 1201 should be a part of “AC-2DPhC” 1001 cleaved.

[0092] As shown in FIG. 12, when a part of AC-2DPhC was cleaved and a parallel beam was incident as in FIG. 10, the output beam 1011 and 1013 shown in FIG. 1, 1213 and 1215 output from the cleaved end face, and output beam 1205 is It was confirmed that the intensity was lower than that of the output beam 1005. Similarly, it was confirmed that the intensity of the output beam 1208 was lower than that of the output beam 1008. It was also confirmed that when the incident position was changed in the X direction, the light leakage intensity from the cleaved end face changed, and the intensity ratio of the leakage light beam changed. From this result, it can be seen that the one-dimensional multilayer film part acts as a weak light confinement mechanism for in-plane propagation light. It can also be seen that the space (uniform) outside the cleaved end face also becomes a light confinement mechanism.

[0093] Furthermore, using an AC-2DPhC equivalent to Fig. 1 with a hydrogenated amorphous silicon (hereinafter “a-SH”) and silicon dioxide (hereinafter “S i 0 ₂ ”) having a period in the X direction of 500 nm. When the sum of the transmitted light and reflected light was measured for the central beam, the wavelength produced by the dip was the same as the wavelength at which the influence of the band of the antisymmetric mode in the vertically grown PhC exists in the same film configuration. It was confirmed that there was. Note it is necessary to use a tunable laser, using 1 equivalent of AC-2DPhC by aS H and S i 0 _2.

 [0094] Figure 13 shows the propagation of the emitted light when a parallel beam with a Gaussian intensity distribution by a laser beam with a wavelength of 532 nm is vertically incident on the "AC-2DPhC" 1201 formed on the substrate 1202 shown in Figure 12 FIG. Fig. 13 (a) is a front view and Fig. 13 (b) is a side view.

 In the figure, reference numeral 1301 denotes an incident parallel beam, reference numerals 1302 to 1305 denote light transmitted in the thin film surface, and reference numerals 1306 to 1308 denote output beams. Fig. 13 shows only characteristic light propagation. When we tried to make light incident from the cleaved end face as shown in Fig. 13, we confirmed the following.

 First, light propagates in the thin film plane.

 Second, it reflects off the boundary between AC-2DPhC and the one-dimensional multilayer.

 Third, light leaks in the Z direction.

[0096] Also, the Pr C and BAS shown in Fig. 2 are similar, and the first PTV is made of AC-2DPhC consisting of 350 nm of P r C and BAS on a fused silica substrate with a thickness of 0.5 mm. As a result of evaluating the branching of light at normal incidence, a branching interval of 1.7 mm was confirmed at a wavelength of 405 nm. However, no branching was observed at any of the wavelengths 473 nm, 532 nm, and 660 nm.

Hereinafter, the light propagation shown in FIGS. 10 to 13 will be described with reference to the drawings.

 FIG. 14 is a model diagram in which light propagation between the “AC-2DPhC” 1001, the one-dimensional multilayer film 1003 and the air formed on the substrate 1002 shown in FIG. 10 is enlarged. In the figure, reference numeral 1401 represents AC-2DPhC, reference numeral 1402 represents a quartz substrate, reference numeral 1403 represents a one-dimensional multilayer film, reference numeral 1404 represents incident light, and reference numerals 1405 to 1423 represent light rays.

[0098] Light ray 1404 incident from the air is the first-order diffracted light 1405 to 1408, light ray 1409 following Snell's law inside AC-2DPhC1401, and light ray propagating parallel to the film of AC-2DPhC 1401 141 1 to 1412, branched to reflected light (not shown).

 The first-order diffracted light beam 1405 is totally reflected at the interface between “AC-2DPhC” 1401 and air, and then enters the interface between “AC-2DPhC” 1401 and substrate 1402. At this interface, it is branched into reflected light and transmitted light 1416.

 Similarly, the first-order diffracted light beam 1406 enters the interface between “AC-2DPhC” 1401 and the substrate 1402, and is split into reflected light beam 1414 and transmitted light beam 1415.

 Similarly, the first-order diffracted light beam 1407 is totally reflected at the interface between “AC-2DPhC” 1401 and air, and then enters the interface between “AC-2DPhC” 1401 and the one-dimensional multilayer film 1403. At this interface, the light is branched into reflected light 1419 and transmitted light 1420.

 In addition, light 1412 propagating parallel to the AC-2DPhC 1401 film (in the direction parallel to the X axis) is incident on the interface between AC-2DPhC 1401 and the one-dimensional multilayer film 1403, and part of it is transmitted. If the output of ray 1415 is not desirable, the output can be reduced by the following method.

 ■ Increase the effective refractive index of AC-2DPhC.

 ■ Metal material is used for the substrate. Or through a metal layer between the substrate and the periodic structure

(3) A material having a low refractive index is used as the substrate.

FIG. 15 is a model diagram in which the propagation of light between the “AC-2DPhC” 1401, the one-dimensional multilayer film 1403 and the air formed on the substrate 1402 shown in FIG. 14 is enlarged. In the figure, reference numerals 1501 to 1502, 1504 to 1509, and 151 1 denote light beams, respectively. Is the interface between “AC-2DPhC” 1401 and substrate 1402, and reference numeral 1510 is the interface between substrate 1402 and one-dimensional multilayer film 1 403.

 “AC-2DPhC” The light 1415 transmitted through the interface between the substrate 1401 and the substrate 1402 enters the interface between the substrate 1402 and the air and is totally reflected. Then, it is incident again on the interface between “AC-2DPhC” 1401 and the substrate 1402, and part of it is transmitted into “AC-2DPhC” 1401 to generate rays 1 504 and 1505 in accordance with reciprocity requirements. This is the process of generating the branched light.

 On the other hand, the light 1423 transmitted through the interface between “AC-2DPhC” 1401 and the substrate 1402 enters the interface between the substrate 1402 and the air and is totally reflected. Next, the light enters the interface between the one-dimensional multilayer film 1403 and the substrate 1402 and is totally reflected. Therefore, the light beam 1423 is confined in the substrate 1402.

[0100] Hereinafter, the relationship between the wavelength dependence of the light propagation and the band structure will be described.

 From the wavelength dependence of light propagation described above, in-plane propagation occurs in the second band of antisymmetric like mode in Fig. 5 corresponding to the second band of antisymmetric mode in Fig. 4. In the first band of the antisymmetric like mode in Fig. 5, which corresponds to the first band of the antisymmetric mode, the same propagation as that of the bulk plate made of a homogeneous medium occurs. In Fig. 5, the band structure near the wavelength where the first band of antisymmetric like mode exists is the same as the band structure near the wavelength where the first band of antisymmetric mode exists in Fig. 4. The band structure in the vicinity of the wavelength where the first band of the like-like mode exists has a large deviation from the band structure in the vicinity of the wavelength where the second band of the anti-symmetric mode of vertical growth exists. We conclude that the second mode of like mode or higher-order antisymmetric like mode band propagates light as described below at the wavelength where it exists.

[0101] The difference between the above-described light propagation and the conventional diffraction grating will be described.

 In conventional diffraction gratings, it is known that diffracted light that satisfies the condition I sin 0 |> 1 (0 is the diffraction angle) is localized as near-field light on the diffraction grating surface (interface between the diffraction grating and air). Yes.

The present invention is different in that it propagates as propagating light not inside the interface but inside P h C. [0102] Fig. 16 is a diagram showing a model of BAS in which the distribution of P r C and the medium distribution of PTV in AC-PhC are all orthogonal to each other. Fig. 16 (a) is a graph showing P r C. The first PT V1601 is parallel to the X direction and has a length of 410 nm, and the second PT V1602 is parallel to the Z direction and has a length of 410 nm. 250 nm. The third PTV is parallel to the Y axis and the length is arbitrary (undefined). Reference numerals 1603 to 1606 denote lattice points. FIG. 16 (b) is a diagram showing the BAS, which is a cross-sectional view in a plane parallel to the ZX plane. The BAS consists of a region 1607 occupied by a medium with n = 2.4, a region 1608 and a region 1609 occupied by a medium with n = 1.5. However, as a periodic structure, region 1608 and region 1609 are continuous, and BAS is essentially composed of two regions.

 [0103] The periodic structure corresponding to the first to tenth inventions is not limited to the periodic structure of PrC and BAS shown in FIG. In general, P r C and BAS shown in Fig. 16 or P r C and BAS shown in Fig. 16 are three-dimensionally extended and the periodic structure corresponding to the first to tenth is also used. is there. When all P TV are orthogonal, the corresponding periodic structure is limited to BAS with a biased medium distribution. The band structure of the periodic structure of PrC and BAS shown in Fig. 16 is similar to the band structure of the periodic structure of PrC and BAS shown in Fig. 2.

 [0104] Here, we will supplement the difference between P h C and P r C and B AS of crystals due to the periodic arrangement of atoms. As shown above, P h C has a shape of P r C and a large degree of freedom in BAS. Such features can be said to be greatly different between crystals based on periodic arrangement of atoms and P h C. In terms of P r C, crystals with a periodic arrangement of atoms basically have a three-dimensional structure, and it is difficult to make a two-dimensional periodic structure like P h C. It is the same.

 [0105] BAS is limited by the electron's orbit in crystals with a periodic arrangement of atoms, whereas in P h C, the constituent medium itself retains its shape, so basically only if it meets the manufacturing process. There is no limit.

[0106] Further, as a difference in appearance of the periodic structure, the periodic structure showing the light propagation has an uneven appearance similar to the play of color seen in gem opal. In contrast, the periodic structure described in Non-Patent Document 4 is transparent. It had a uniform appearance (similar to translucent colored glass), although it had a color reflecting the reflection spectrum.

 [0107] So far, the propagation characteristics of the electromagnetic waves of the periodic structures according to the eleventh to fifteenth inventions have also been clarified. Therefore, the propagation of light from (A) to (J) is collectively referred to as H-type propagation. Also, when referring to individual items in H-type propagation, for example, when referring to (A) above, it is abbreviated as H-type propagation (A).

 [0108] Further, the following assistive technology may be added to the first to fifteenth inventions. As already described, in the periodic structure according to the first to seventh inventions, the light propagation described in H type propagation (A) to H type propagation (D) occurs. As shown in (L), there is a close relationship with the antisymmetric mode of a similar structure having a mirror surface, and controlling the wavelength in which the band of the antisymmetric mode exists can control the H-type propagation (A) ~ A means to control the wavelength at which the light propagation described in H type propagation (D) occurs.

 [0109] In response to this, we examined “a method of extending the wavelength band in which anti-symmetric mode bands exist” in P h C by PrC and BAS equivalent to those in FIG. It is already known that the following two points dominate the wavelength where the band of antisymmetric mode exists, and the influence of other parameters on P r C is small (see Non-Patent Document 6).

 (1) PTV length perpendicular to or near the incident direction (in AC-PhC, the period of irregularities formed on the substrate)

 (2) Refractive index and filling ratio of medium used (effective refractive index)

 [0110] Based on the above, a simulation was performed. In general, a periodic structure with a refractive index distribution in PrC or BAS with a complicated configuration is used to extend the wavelength band where the band of antisymmetric mode exists. Was found to be advantageous.

 [0111] In the following, particularly effective methods for expanding the wavelength band are listed with reference to the drawings.

As the first effective method, 3D P h C is used. 3D P h C is more advantageous than 2D P h C because the number of anti-symmetric mode bands increases as the number of directions with discrete translational symmetry and period size increases. . In particular It is desirable that each PTV has a different length.

[0112] As a second effective method, B AS including a medium having three or more kinds of refractive indexes is used. This means can be realized by using three or more types of media and setting the manufacturing conditions appropriately.

[0113] As a third effective method, refractive index modulation exists twice or more in the light traveling direction.

Use B A S.

 [0114] For example, if the regions 114, 116, 118, 120, and 122 in Fig. 1 are changed to a medium of n = 3.4, the refractive index modulation exists twice. In addition, since it is Pr C and B AS of AC-PhC, it can easily cope with the first to tenth inventions.

 [0115] Or, for example, the thickness of regions 114, 116, 118, 120, 122 in FIG.

 If the thickness is changed sufficiently to the thickness of 115, the refractive index modulation exists twice.

 [0116] The fourth effective method is to optimize the parameter of PrC so that the photonic band gap is narrow, the band is folded back, and the group velocity of light in the antisymmetric mode band is reduced.

 Note that the above-mentioned “method of extending a wavelength band in which an antisymmetric mode band exists” can be used not only independently but also in combination. Conversely, if it is desirable that the wavelength band where the antisymmetric mode band exists is narrow, such as when generating H-type propagation (E) only at a specific wavelength, the above procedure may be reversed.

 [0118] 4. Description of the sixteenth through nineteenth inventions

 Hereinafter, the sixteenth to nineteenth inventions will be described in detail with reference to the drawings.

Regarding the sixteenth invention, for example, in FIG. 2, silicon (hereinafter referred to as S i) is used instead of the medium of n = 2.4 that occupies region 207, and n = 1. occupies region 208 and region 209. This can be explained by an example using silicon carbide (hereinafter referred to as S i C, p-type semiconductor) in place of medium No. 5. A pin junction can be formed by forming an intrinsic semiconductor layer (i layer) and an _n- type semiconductor layer ( _n layer) on the Si. Since the refractive index of the i layer and n layer in the Si is almost the same, the periodic structure with two media for light Act as a body.

[0120] With respect to the seventeenth invention, for example, in Fig. 2, Si is used instead of the medium of n = 2.4 that occupies the region 207, and the transparent guide is replaced with the medium of n = 1.5 that occupies the region 208. Using tin oxide (hereinafter referred to as Sn0 ₂ , n-type semiconductor), Si C instead of the medium of n = 1.5 that occupies the region 209, an intrinsic semiconductor layer (i Layer) and an _n- type semiconductor layer (n layer). The periodic structure in this case has electrical conductivity in the Z direction. Since the refractive indexes of S i C and Sn0 ₂ are almost the same, they behave as a periodic structure with two media for light.

 [0121] The eighteenth aspect of the invention can be explained by an example in which one medium is a fluid (gas, liquid) and the other medium is a solid among the medium of the periodic structure showing H-type propagation. The fluid includes air, liquid, etc. If it is a fluid, it can be moved in and out of the periodic structure, and the H-type propagation or E-branch (E) branching occurs when the fluid is replaced. The interval can be changed.

 [0122] The nineteenth invention can be explained by an example using either a nonlinear optical material or a luminescent substance as a medium having a refractive index n = 1.5 or a medium having a refractive index n 2.4 in FIG. . H-type propagation (A) to (D) In other words, it is the effect of confining light within the periodic structure. By confining light, the electric field strength in the periodic structure increases, and the interaction between the medium and light can be increased compared to a homogeneous medium. That is, if the constituent medium of the periodic structure has an optical polarizability having nonlinearity, the efficiency of the nonlinear optical effect can be increased. Furthermore, if the constituent medium of the periodic structure contains a light-absorbing substance, the absorption efficiency can be increased. In the periodic structure, since the light intensity distribution is concentrated on the high refractive index medium, the other medium combined with the nonlinear optical material, light emitting substance, and light amplifying substance is a nonlinear optical material, light emitting substance, light. It is desirable that the refractive index be lower than that of the amplifying material.

 [0123] 5. Description of the 20th and 21st inventions

Hereinafter, the twentieth and twenty-first inventions will be described in detail with reference to the drawings. [0124] As described above, the peripheral structure of the periodic structure also serves as a means for controlling the propagation of light. The following three types of periodic structures are available as effective periodic structures.

 (a) Heterojunction of periodic structures with different lengths of P r C, directions of P r C, and number of dimensions. In other words, periodic structures with different PTV sums, so-called composite vectors, are joined. It is desirable that the constituent media in each periodic structure to be joined at this time are the same, and the same type of constituent media in each periodic structure be continuous (corresponding to the twentieth invention).

 (b) Structure in which the end face of the periodic structure is connected to a uniform medium (corresponding to the twenty-first invention)

) o

 (c) A structure in which PhCs with different periods and medium configurations are connected in series in the direction of the third PTV.

 The twentieth invention can be explained by a combination of “AC-2DPhC” 1001 and planar multilayer film 1003 shown in FIG. 10, for example. “AC-2DPhC” 1001 has a substantial period in two directions, and the planar multilayer film 1003 has a substantial period only in one direction in the Z direction. “AC-2D PhCj 1001 and planar multilayer film 1003 are both multilayer films, and each layer is continuous with each other.

[0126] Periodic structures with different PTV sums include periodic structures with different P r C lengths, different P _r C directions, or different dimensions.

[0127] The effect of the twentieth invention is that, as described above, the sum of PTV is different so that the planar multilayer film 1003 has the effect of confining light propagating in the thin film surface of AC-2D PhCj 1001. Light can be transferred (transmitted and reflected) at a constant rate between the two periodic structures, and the rate can be controlled by the length and direction of the PTV. Instead of 1003, by placing appropriate 3D self-cloning photonic crystals around the AC-2DPhC 1001, the output beams 1011 to 1012 in Fig. 10 can be suppressed. The twenty-first invention can be explained by a combination of “AC-2DPhC” 1401 shown in FIG. 15 and the surrounding air or quartz substrate 1402. The atmosphere is a uniform medium of n 1.0. H-type propagation (C) and (E) are manifested in combination with the surrounding atmosphere and the quartz substrate 1402. Further, if the cleaved end portion in FIG. 12 is coated with metal, the output beam 121 1 can be suppressed.

 With regard to the structure of (c), for example, on the region 123 in FIG. 1, a thin film with a thickness of 120 nm by a medium having a refractive index n = 1.5 and a thickness by a medium having a refractive index n ½2.1 is 90 nm. For example, the thin films may be alternately stacked while the uneven shape of the region 123 is maintained.

 [0130] The following effects can be obtained by joining periodic structures with different sums of P T Vs in the Z direction. First, multiple P h Cs with different PTV directions are connected in series to obtain multiple beam branching directions that proceed in the same direction as transmitted light according to Snell's law, for example, by H-type propagation (E). It is done. Next, by connecting multiple P h Cs with different constituents or periods on the XY plane in series, for example, the above-mentioned H-type propagation (E) can be obtained in a wide wavelength range. In the case of AC-PhC, the heterostructure PhC has already been realized by changing the period of unevenness for each region in the substrate and changing the thickness of the multilayer film (see Patent Document 1). )

 [0131] 6.22 of

 Hereinafter, the twenty-second invention will be described in detail with reference to the drawings.

[0132] In order to develop the H-type propagation, it is preferable to prepare the periodic structure according to any one of the first to fifteenth inventions in a large area. It is desirable to use -PhC. In fact, in the AC-PhC having the structure shown in FIG. 1, in general, the average incident direction of deposition or etching particles is inclined with respect to the substrate. It is possible to prepare a periodic structure of the invention with a large area. A specific manufacturing method will be described below with reference to the drawings.

[0133] FIG. 17 shows the direction of the substrate and the deposited or etched particles incident on the substrate. It is a front view. Reference numeral 1701 denotes a convex portion formed on the substrate, reference numeral 1702 denotes a concave portion formed on the substrate, and reference numeral 1703 denotes an average incident direction of deposited particles or etching particles. Reference numerals 1704 and 1705 denote vertices of the convex portions.

FIG. 18 is a top view showing the substrate and the direction of deposited particles or etching particles incident on the substrate. Reference numeral 1801 denotes the upper surface of the substrate, reference numeral 1802 denotes the average incident direction of the deposited particles or etching particles, and reference numeral 1803 denotes the direction of the period of the irregularities formed on the substrate.

 FIG. 19 is a top view showing the positional relationship between the target and the substrate. Reference numeral 1901 indicates a target, reference numeral 1902 indicates a substrate, reference numeral 1903 indicates the direction of the period of the irregularities formed on the substrate, and reference numeral 1904 indicates the average incident direction of the deposited particles, etching particles, or etching particles.

 FIG. 20 is a front view and a side view showing the positional relationship between the target and the substrate and the incident direction of the deposited particles, etching particles, or etching particles. Fig. 20 (a) is a front view and Fig. 20 (b) is a side view.

 [0137] The twenty-second invention can be explained by the incident directions of the substrate and deposited particles or etching particles with respect to the substrate shown in FIGS. 17 to 20, for example. In manufacturing the AC-PhC shown in Fig. 1, the deposited particles or etching particles are averaged in the incident direction on the substrate with irregular or sawtooth two-dimensional or one-dimensional period as shown in Fig. 17. Manufactured with a film formation process in which values are concentrated in a specific direction (anisotropic deposition or anisotropic etching), and the average incident direction 1703 of the incident angle of deposited particles or etched particles with respect to the substrate is oblique to the substrate. It is desirable to have it. Further, as shown in FIG. 18, the angle formed by the period 1803 of the unevenness formed on the substrate 1801 and the average incident direction 1802 of the deposited particles or etching particles is between 0 ° and 45 °, preferably 0 ° to 10 °, Most preferably, it is 0 degree. When the angle is 0 degree, the angle between the second PT V202 in Fig. 2 and the XY plane (including the first and third PTV) is minimized, and the degree of symmetry breaking is maximum. It becomes.

[0138] The simplest method for a two-dimensional periodic structure is shown in Figs. 19 and 20. The substrate is placed off the axis of the target (displaced from directly above), and the direction of the period 1903 formed on the substrate and the direction connecting the center of the cylindrical target 1901 and the center of gravity of the substrate are parallel to each other It is to arrange so that the sputtering method is used. In the sputtering method, the deposition particles that jump out of the target have directionality (the direction in which the particles fly is not random), and the deposition particles scattered off the axis of the target have directivity in the direction of the average incident direction 1904. As a result, more particles are accumulated at the vertex 1705 of the convex portion than at the vertex 1704 of the convex portion, resulting in the AC-2DPhC shown in FIG.

 [0139] Regarding the three-dimensional periodic structure, non-patent literature on the outside of the target (off-axis)

 A substrate with an in-plane pattern with a two-dimensional period of a square lattice as described in Fig. 3 (b) on page 231 is arranged, and the direction of the period formed on the substrate and the deposited particles or etching It is convenient to arrange the particles so that the average incident directions are about 45 degrees. On the other hand, in order to obtain a desired propagation direction, it is possible to use an angle formed by the direction of the period formed on the substrate and the average incident direction of the deposited particles or the etching particles.

 [0140] For example, the angle formed by one of the average incident direction of deposited particles or etched particles and the period of irregularities (period 1) is 0 degrees, and the average incident direction of deposited particles or etched particles and the period of irregularities If the other angle (with period 2) is 90 degrees, the propagation of H-type propagation (A) and (E) occurs only in the direction of period 1. If the angle between the average incident direction of deposited particles or etched particles and the period 1 is 45 degrees, the propagation of H-type propagation (A) and (E) occurs in the direction of the period 1 and period 2. The ratio of the intensity of the H-type propagation (E) light generated in the direction of period 1 and the intensity of the H-type propagation (E) light generated in the direction of period 2 can be adjusted by the angle value.

 [0141] On the other hand, the deposition particles have directivity in the direction perpendicular to the substrate, and the etching particles are incident obliquely with respect to the substrate (having directivity in a direction not perpendicular to the substrate). The periodic structure described in 1 can be produced.

[0142] In addition, as a manufacturing method of two-dimensional P h C using P r C shown in FIG. This can be achieved by depositing a film by a self-cloning method on a substrate having irregularities such as a distorted diffraction grating. As a method for manufacturing a substrate having irregularities such as a blazed diffraction grating, it is effective to perform sputter deposition under conditions suitable for a step-type blazed diffraction grating. The positional relationship between the target and the substrate may be directly above. Note that a substrate having a cross-sectional shape such as a blazed diffraction grating can also be produced by nanoimprinting.

 [0143] 7. Description of the 23rd to 25th inventions

 Hereinafter, the twenty-third to twenty-fifth inventions will be described in detail with reference to the drawings. The above first to twenty-first inventions can be further expanded in application range by combining with other related technologies and other devices.

 [0144] The first to fifteenth inventions do not exhibit their functions without a separate electromagnetic wave source (light source). In addition, since the 11th to 14th inventions have polarization dependency due to the breaking of symmetry, it is effective to separately use them in combination with a polarization separation element, a polarizer, or a phase plate. In addition, it is effective to combine it with a reflection means such as a lens or a metal mirror, which is a conventional device for controlling the propagation of light.

 [0145] On the other hand, if the beam is reciprocated between the combination of the periodic structure showing the H-type propagation and the mirror, the number of beams can be increased to the number of equations. In addition, if a plurality of parallel beams and lenses generated as a result of H-shaped propagation are combined, a plurality of beams generated from the same light source can be condensed at one point. An optical recording device can be obtained by arranging a photoconductor at this condensed point.

 [0146] In addition, the beams traveling parallel to each other generated by the H-type propagation (E) have almost the same polarization state, but the polarization extinction ratio is deteriorated, so that the polarizer, the reflective polarization separation element, and the walk-off It is desirable to recover the polarization extinction ratio in combination with a type polarization separation element.

[0147] In addition, when light is used for signal transmission, a modulator or a light receiver is required, and it is also effective to combine reflection means and a diffraction grating appropriately. Furthermore, in the case where beams parallel to each other generated by the H-type propagation (E) are used individually, it is desirable to combine them with an optical waveguide. Next, the twenty-fourth invention will be described. If the device according to the twenty-fourth invention is used, a beam emitted from one light source can be incident many times on an optical element having a function of branching one beam into a plurality of beams propagating in the same direction. . Further, if a plurality of optical elements having different beam branching directions are used, the intensity of the beam can be dispersed and made substantially uniform within the effective range of the optical elements. The same effect can also be obtained by combining the periodic structure that generates the H-shaped propagation, which is branched into a plurality of beams propagating in the same direction, and a reflective polarizer, a mirror, a wave plate, and the like. it can. Note that there may be a plurality of beams incident from the outside first.

 Next, the twenty-fifth aspect of the invention is described. The twenty-fifth invention is effective as an optical recording apparatus, for example. In some cases, the device may include a charge coupled device array light receiver, a CMOS sensor array, or reflecting means having the same reflection direction as the periodic structure. In particular, the periodic structure splits incident light into two or more beams propagating in the same direction, and at least one of the two or more beams transmits or reflects the spatial light modulator, A device in which at least two beams including the beam transmitted or reflected from the spatial light modulator among the two or more beams are condensed at the same location in the photosensitive member via the lens is effective as an optical recording apparatus. It is. In particular, if a single lens is used with the function of splitting a single beam into multiple beams propagating in the same direction, the two beams can be accurately focused at one point (however, the spread of the spot is ignored) ) Furthermore, if two-dimensional intensity distribution change is given to one or both of the two beams, it can be used for holographic recording.

 [0150] 8. The name of phonic moth, mode, and force of ¾ΒΨ¾ί leather ¾0 force Furthermore, the inventor is about "Method to control coupling efficiency of anti-symmetric mode of Ph C and external plane wave" Also examined. The following (1) and (2) are known in Non-Patent Document 4 and can be used as they are.

(1) The coupling efficiency between the antisymmetric mode of P h C and the external plane wave depends on the incident angle. (2) The coupling efficiency between the antisymmetric mode of P h C and the external plane wave depends on the number of layers (number of periods).

 [0151] The matters described so far centering on light are applicable to electromagnetic waves in general.

[0152] As described above, the peculiarities of the periodic structure according to the first to nineteenth inventions have been clarified. Therefore, in order to distinguish from the conventional periodic structure and P h C, a special name is given to the periodic structure corresponding to the first to tenth inventions. In other words, the Pr C and BAS shown in Figure 2 and the equivalent P r C and BAS are “2D-collapsed ACBC”, and the “2D-collapsed ACBC” periodic structure is “2D-collapsed ACPC”. Pr C and BAS expanded to three dimensions in Pr C and BAS shown in Fig. 2 "3D-collapse ACBC", and the periodic structure by "3D-collapse ACBC" is "3D-collapse ACPC" Pr C and BAS and equivalent P r C and BAS shown in Fig. 16 are referred to as “2D-inside-down ACBCj” and the “2D-inside-down ACBC” periodic structure is referred to as “2D-inside-down ACPC”. And

 Example 1

 The light propagation control element according to Example 1 of the present invention will be described in detail with reference to the drawings.

The periodic structure formed on the substrate shown in FIG. 1 is used, and Si 0 ₂ is used as a medium with n = 1.5, and niobium pentoxide (hereinafter, Nb ₂ 0 ₅ ) is used as a medium with n = 2.4.

[0154] A manufacturing method of “2D-collapse ACPC” shown in FIG. 1 will be described. The structure shown in FIG. 1 is manufactured by first forming irregularities on the substrate base material, then forming a shaping layer on the substrate, and then laminating a multilayer film in accordance with the self-cloning method and the twenty-second invention. it can.

 [0155] First, the substrate 124 will be described. FIG. 21 is a schematic perspective view showing the substrate 124 shown in FIG. Reference numeral 2101 denotes a substrate base material, and reference numeral 2102 denotes a concave-convex convex portion formed on the substrate base material. The periodicity of the irregularities formed on the substrate base material has only in the X direction and is uniform in the Y direction.

 [0156] A fused silica is used as the material of the substrate 124, and an electron beam is placed on the flat fused quartz substrate.

(Hereinafter referred to as EB) 410nm period in lithography process and dry etching by exposure A rectangular irregularity (hereinafter referred to as a substrate pattern) having a convex part (projection part height and width of 205 nm) is formed. Complementing the method of forming a substrate pattern on the substrate, a process that combines lithography and etching by EB, a process that combines lithography and etching by light or X-ray exposure, or a nano-imprinting method can be used. In addition, if an opaque material film is used in a UV layer that is sufficiently thick and laminated on a substrate that is opaque in the UV region or a transparent substrate, unevenness on the substrate can be produced even in a process that combines interference exposure and etching. Can be formed. In this embodiment, it is preferable to employ a process in which lithography and etching using EB are combined with a fused silica substrate because etching is easy and etching is excellent in shape accuracy.

[0157] Next, the intermediate layer (shaping layer) 112 will be described. FIG. 22 is a diagram showing the substrate 124 and the shaping layer 112 shown in FIG. Reference numeral 2201 represents the substrate shown in FIG. 21, and reference numeral 2202 represents the shaping layer (same as the intermediate layer 112). The periodicity is only in the X direction. After forming irregularities on the substrate shown in FIG. 21, deposit an S i 0 ₂ film on the substrate by rf-bias sputtering (rf sputtering with effect of sputter etching) under appropriate conditions. To form a triangular shaped shaping layer. At this time, as shown in FIGS. 19 and 20, the substrate is removed from right above the target, and the radial direction of the target and the periodic direction of the substrate are made substantially the same direction, so that the cross section in the ZX plane is a non-isosceles triangle. (Triangles with different lengths on three sides) A shaped shaping layer can be realized.

Next, a multilayer film composed of the Si 0 ₂ layers 101 to 11 1 and the Nb ₂ 0 ₅ layers 113 to 123 shown in FIG. 1 will be described. If Nb ₂ 0 ₅ and S i 0 ₂ are alternately laminated on the substrate on which the shaping layer 2202 shown in FIG. 22 is laminated, the cross-sectional shape shown in FIG. 1 is obtained. S i 0 ₂ layer and Nb ₂ 0 ₅ layer are stacked by rf bias sputtering. Figure 23 is an electron microscope of the cross section in the ZX plane of the 2D self-cloning P h C (2D-collapsed ACPC) actually fabricated. It is a photograph. The stacking cycle is 11 cycles. In Figure 23, the layer with the appearance close to white is Nb ₂ 0 ₅ layer, and the layer with the appearance close to black is S i 0 ₂ layer The substrate and the shaping layer are indistinguishable because they are made of the same composition material.

 [0160] According to Fig. 23, it can be seen that the growth direction of the film is inclined by about 4 degrees. In Fig. 23, the shape is not stable up to the initial third layer of the multilayer film, and the shape is stabilized from the fourth layer, but there is no problem. The direction of film growth is the direction of the third PTV, and the direction in which the third PTV is projected onto the XY plane in Fig. 1 is the direction in which the propagation or branching of light from H-type propagation (A) to (E) occurs. Become.

[0161] Next, a supplementary description of a method for manufacturing a periodic structure will be provided. When stacking Nb ₂ 0 ₅ films, the target is, for example, an Nb _{2 5} sintered body, the deposition gas is, for example, a mixed gas of argon and oxygen, and the gas pressure is, for example, 0.3 Pa to 1. OPa ( It is preferably 0.4 Pa to 0.8 Pa, more preferably 0.5 Pa to 0.7 Pa, which is a condition that balances the residence stress and density of the film.) The oxygen gas flow rate ratio is, for example, about 10% ( It is preferably 5% or more and 20% or less, and more preferably 7% or more and 15% or less under conditions that balance the film formation rate (the amount of increase in film thickness per hour) and the stability of the composition. When the S i 0 ₂ film is laminated, the target is, for example, quartz, the deposition gas is, for example, a mixed gas of argon and oxygen, and the gas pressure is, for example, 0.33 to 2.03 (preferably 0 6 Pa to 1.8 Pa, and more preferably 0.8 Pa to 1.5 Pa, which is a condition that balances the residence stress and density of the film. The bias to be applied is preferably about several tens of volts, although the optimum value depends on other film formation conditions and the apparatus. The substrate heating temperature in the thin film process is usually desirably 0.3 times or more of the melting point of the medium, but is preferably 0.3 to 0.5 times, more preferably the film density and heating cooling. The balance of the time required for this is 0.31 times or more and 0.4 times or less. In this embodiment, the substrate heating temperature is preferably about 600K.

 [0162] In addition, the rf bias sputtering method, ECR sputtering method, rf magnetron sputtering that does not apply bias on a substrate shaped into a pillar type, and sputtering, ion gun, RIE, and other etching combinations can also be used for 2D-transverse. Breaking ACPC can be made.

[0163] Note that the growth direction of the film (equal to the PTV direction) depends on the radial direction of the target. It can be controlled by changing the angle between the periodic directions of the plate, and it can also be controlled by the distance between the target and the substrate. In addition, “3D-collapse ACPC” can control the direction of PTV by adjusting the angle between the average incident direction 1802 of etching particles in FIG. 18 and the period 1803 of irregularities between 0 degrees and 90 degrees, for example. .

In this example, Nb ₂ 0 ₅ was used as a high refractive index medium in P h C, but SiC, Si Ox (where 0 <x <2), tantalum pentoxide (Ta ₂ 0 ₅ ), titanium dioxide (Ti0 ₂ ), gallium nitride (GaN), aluminum nitride (AIN), zinc oxide (ZnO), ZnSe, ITO (Indium Thin Oxide), hafnium oxide (Hf0 ₂ ), a-Si0, SiN, etc. It is also effective to use a combination of any of n≥2. It is also effective to use a combination of n ≤ 1.6 media such as magnesium fluoride (MgF) and calcium fluoride (CaF) as the low refractive index medium.

 [0165] The periodic structure shown in Fig. 1 (and Fig. 23) exhibits the H-type propagation. FIG. 24 is a graph showing the transmittance wavelength dependency of the periodic structure formed on the substrate shown in FIG. 1 when the beam transmitted according to Snell's law is perpendicularly incident. Figure 24 (a) shows the corresponding characteristics when the incident beam is TE polarized, and Figure 24 (b) shows the characteristics when the incident beam is TM polarized. As shown in Fig. 24 (a) and (b), the periodic structure shown in Fig. 1 (and Fig. 23) has a transmittance wavelength dependency different from that of conventional optical elements such as diffraction gratings and wavelength selective filters. I understand.

 The present embodiment uses an H-type propagation (E) to install an optical fiber with a lens at, for example, an incident position of light and an outgoing position of branched light, thereby providing an optical branching device used for optical communication. Available as (star power bra). In addition, by splitting the parallel beam from one laser light source into three, a three-beam pickup for tracking and reading / writing can be easily realized and used for optical recording devices.

[0167] In addition, by using H-type propagation (I), if beams of different wavelengths are incident on the same direction in the same direction and with a separation distance of each wavelength from the Z direction, Can be used as a synthesis mechanism, for example reading signals from DVD and CD The structure of the pick-up can be simplified.

 In addition, if a beam having a wide spectrum is incident from the z direction with respect to this embodiment, it can be used as a wavelength branching mechanism, for example, as a spectroscope.

 [0168] Further, as another invention, if the periodic structure that generates the H-shaped propagation (E) is used and the same number of lenses as the beam are used, it corresponds to a plurality of types of optical recording disks that use the same wavelength. One pickup can be realized.

 Example 2

 A holographic optical recording apparatus according to Embodiment 2 of the present invention will be described in detail with reference to the drawings. This embodiment is a holographic optical recording apparatus using H-type propagation.

 FIG. 25 is a side view showing the basic configuration of the holographic recording apparatus. The holographic recording device is composed of a laser light source 2501, a lens 2502, a periodic structure 2503 having an optical branching function by H-type propagation (E), and a spatial light modulator integrated adjacent to each other DMD2504 (digital micromirror device) ), A mirror 2505, a reflective polarization separation element 2506, a 1Z4 wavelength plate 2507, a lens 2508, a recording medium 2509, and a two-dimensional image sensor (CMOS sensor). In the following, devices with optical branching function by H-type propagation (E) to H-type propagation (K) are abbreviated as “HBS”.

FIG. 26 is a side view showing the operation during recording. Reference numeral 2601 is an incident parallel beam to H BS2503, reference numerals 2602 and 2603 are output beams output from the transmission side of HBS2503, reference numeral 2604 is a beam reflected by a mirror, reference numeral 2605 is a beam reflected by DMD2504, reference numeral Reference numerals 2606 and 2607 respectively denote output beams output from the HBS 2503 to the reflection side.

[0172] The operation during recording will be described with reference to FIG. After the parallel beam output from the laser light source is incident on the HBS, it is output as two parallel propagating beams from the transmission side. After that, one of the two beams is given 2D page data by DMD, and the other beam is reflected by a mirror with a dielectric multilayer film formed on the same substrate as DMD. Then each beam is a common lens Condensed light at the focal point and recorded in the form of interference fringes on a recording medium made of a photosensitive material.

 FIG. 27 is a side view showing the operation during reproduction. Reference numeral 2701 is an incident parallel beam to the HBS 2503, reference numerals 2702 and 2703 are output beams output from the HBS 2503 to the transmission side, reference numeral 2704 is a beam reflected by a mirror, and reference numeral 2705 is a beam reflected by a recording medium 2509. Reference numerals 2706 denote beams reflected by the reflective polarization separation element 2506, respectively.

 [0174] The operation during playback will be described with reference to FIG. A parallel beam output from a laser light source with a lens is incident on H B S and then output as two beams propagating in parallel from the transmission side. After that, all the pixels are turned off by D M D, one of the two beams is blocked, and the other beam is reflected by a mirror made of a dielectric multilayer film formed on the same substrate as D M D. The reflected beam passes through the reflective polarization separation element and the 1 Z 4 wavelength plate, and is then focused at the focal position by the lens, and intensity distribution information is given in the form of interference fringes on the recording medium. The beam to which the information is applied and reflected from the recording medium is reflected by the reflective polarization separation element and enters the two-dimensional image sensor.

 [0175] Signal processing and the like may be the same as those of conventional holographic recording. In principle, the DMD is turned off during playback. However, even if the DMD is on, the DMD reflected light and the mirror-reflected light are incident sufficiently far away from the two-dimensional image sensor, so there is no adverse effect on playback. However, it may be deteriorated because it may deteriorate the photosensitive material of the recording medium.

 FIG. 28 is a diagram showing H B S used in this example. The first region 2801 and the third region 2803 in the HBS are self-cloning 3D Ph C “3D-collapse ACPC”, and the periodic structure of a square lattice with an uneven period on the XY plane of 180 nm Have. The second region 2802 is “2D-collapse A CPC” in which the period of unevenness of the substrate fabricated in the same manner as in FIG. 1 is 205 nm. The fourth region 2804 is a one-dimensional periodic structure. Reference numeral 2805 denotes the incident and outgoing positions of the beam, and reference numeral 2806 denotes the outgoing position of the beam.

[0177] The HBS 2503 will be described with reference to FIG. The first area 2801 in HBS 2503 is It is a self-cloning 3D P h C, and has a square lattice-like periodic structure with an irregular period of 180 nm on the XY plane. The second region 2802 is “2D-collapsed ACPC” in which the period of unevenness of the substrate manufactured in the same manner as in Example 1 is 205 nm. The third area 2803 is the same as the first area 2801. The fourth region 2804 is a one-dimensional multilayer film having no period in the XY direction. The first region 2801 has a band gap at a wavelength of 405 nm, and suppresses leakage light from the second region 2802 in the Y direction. The size of the second region 2802 is 4 mm so that two beams are emitted. The beam emitted to the reflection side can be used for monitoring a laser light source. The second area 2802 may be “2D-inverted ACPC”.

[0178] In general, in holographic recording, as described in Patent Document 2, an optical system with multiple reflections from the same laser light source is used, and information light and reference light are processed by separate components. It is said to be weak against vibration (for example, surface runout that occurs when a disc-shaped disk rotates) and has poor stability against environmental changes. However, if the HBS shown in Fig. 28 is used and the optical system shown in Fig. 25 is used, the information beam and the reference beam are always focused on the same point even if the position and angle of each component are shifted. Is possible.

 Example 3

 An apparatus according to Example 3 of the present invention will be described in detail with reference to the drawings. The present embodiment is an apparatus that performs uniform light intensity distribution and polarization conversion using H-type propagation. The apparatus according to the present embodiment is particularly suitable for use in making the light intensity uniform in a projection display (projector) and in polarization conversion from a non-polarized light source.

 Conventionally, in a liquid crystal projector, linearly polarized light has been obtained from a lamp that is a non-polarized light source using the p s polarization conversion element described in Patent Document 3 and Patent Document 5.

 [0181] In addition, the optical integrator (opt i cal ntegrator. Hereinafter abbreviated as Op l) is used to effectively apply the luminous flux having a circular cross section from the lamp or the reflector attached to the lamp to the rectangular liquid crystal panel. It has been. Examples of Op l include the examples described in Patent Document 4 and Patent Document 5.

[0182] This example uses a periodic structure showing H-type propagation, and has a simple and compact configuration. This is a polarization-compensated Opl (hereinafter abbreviated as rPC-0pl) that equalizes the intensity and converts the polarization and concentrates the output light in one direction.

 FIG. 29 is a side view of PC-0pl and a diagram showing light propagation inside PC-0pl. PC-0pl shown in FIG. 29 has an optical fiber 2901 with a lens, a mirror 2902, a 1Z4 wavelength plate 2903, an HBS group 2904 to 2907, a PhC reflection type polarization separation element 2908, and a light shielding plate 2909. Reference numeral 2910 represents a parallel beam output from the optical fiber with lens / 2901. HBS groups 2904 to 2907 arranged in series with respect to the traveling direction of the beam from the optical fiber 2901 with a lens, a reflective polarization separation element 2908 with a two-dimensional Ph C, and a mirror 2902 with respect to a parallel beam 2910 3 The distance between HB S2904 and mirror 2902 is 20mm.

 [0184] The operation will be described with reference to FIG. First, the output light 2910 from the optical fiber 2901 with a lens is incident on the HBS 2904 via the 1Z4 wavelength plate 2903, branched into three beams on the transmission side, and output. The three beams output to the transmission side of HBS 2904 are incident on the next H B S 2905, and the beams are split into nine beams on the transmission side and output. Thus, the number of beams output to the transmission side increases as the latter HBS is reached.

Furthermore, the output light 2910 from the optical fiber 2901 with a lens enters the HB S2904 via the 1Z4 wavelength plate 2903, and is branched into three beams on the reflection side and output. The three beams output to the reflection side of the HBS2904 pass through the 1 Z4 wave plate 2903, are reflected by the mirror, pass through the 1 Z4 wave plate again, and enter the HBS 2904 again. The light is incident on HBS 2904 again, and the beam is split into 9 beams on the transmission side and output. However, since there are some overlapping beam positions, the actual number of beams is five. In addition, the position where the light is incident again on the HBS2904 and the beam is split into nine beams on the transmission side and output is as follows. It is different from the position where it is split into three beams on the transmission side and output. Although not described, the beam incident on the HBS2904 again is divided into nine beams on the reflection side (actually five beams due to beam overlap) and output. [0186] In this way, the number of beams increases with each repetition of transmission and multiple reflection between HBS, reflection type polarization separation element 2908, and mirror 2902 (such as, for example, a chain reaction in fission). .

 [0187] Because there are many beams that are repeatedly reflected and branched between the HBS, the reflective polarization separation element 2908—between the HBS, and between the HBS mirrors, the light that has passed through the reflective polarization separation element 290 8 is a large number of beams. The intensity distribution with the overlap is linearly polarized light.

 [0188] Since the mirror 2902, the HBS 2904 to 2907, and the reflective polarization separation element 2908 are arranged in parallel, and the incident light is a parallel beam, the light transmitted through the reflective polarization separation element 2908 is so-called telecentric light. It becomes. Furthermore, if a large number of optical fibers with lenses are installed, almost uniform light can be obtained in a larger area. Further, the light shielding plate 2909 can block light having low uniformity in the outer peripheral portion of the light transmitted through the reflective polarization separation element 2908.

 [0189] The H B S group will be described. “2D-collapsing ACPC” in the H B S group has 45 degrees of light splitting direction, and each has a beam separation function of 2 mm. In addition, a one-dimensional planar multilayer film that blocks in-plane propagation is placed around “2D-collapse ACPC”. However, in order to cut off the in-plane propagation more efficiently, it is effective to use a three-dimensional periodic structure or a metal film instead of a one-dimensional planar multilayer film, although this increases production costs. Although the manufacturing cost also increases, the uniformity of output light in FIG. 29 improves as the number of H B S increases.

[0190] Other components will be described. The optical fiber with lens 2901 is connected to a green laser light source, and the beam diameter of the output beam is 1 mm. The reflective polarization separation element 2908 has a function of selecting the final output light as linearly polarized light having a predetermined direction, and the polarization component orthogonal to the polarization direction of the output light included in the incident light to the polarization separation element is reflected. It is incident on the HBS again. The reason why the two-dimensional PhC is used as the reflection type polarization separation element is that the transmittance and the reflectance can be set arbitrarily. The transmittance in the direction of the transmission polarization is about 40% (preferably 20% or more and 60% Or less, more preferably 30% or more and 50% or less). The degree distribution can be made uniform.

 [0191] Mira 1902 is made of a dielectric multilayer film, and the multilayer film is removed only at the light incident position from the optical fiber with lens / 2901, reflecting the return light of the periodic structure having the optical branching function. Has the effect of Although a mirror with an aluminum film attached on a transparent glass plate can be used, it is a flat mirror, and a dielectric multilayer film is more suitable because it does not absorb light. The 1 Z 4 wavelength plate 2903 has a function to change the polarization state. The light reflected by the reflective polarization separation element 2908 is transmitted through the 1 Z 4 wavelength plate 2 903, reflected by the mirror 2902, and again 1 Z 4 The light that has passed through the wave plate 2903 passes through the reflective polarization separation element 2908 at a high rate.

 [0192] The effect of the present embodiment will be described. If the configuration shown in Fig. 29 is used, the intensity distribution is made uniform by repeating the branching and reflection of the beam, and the output light is linearly polarized. Furthermore, since the reflecting element arranged in parallel with the parallel beam and a periodic structure having a light branching function for branching the incident light into a plurality of beams propagating in parallel, the output light has a number of parallel beams propagating in the same direction. The intensity distribution is maintained even in the distance after the light is transmitted. In general, the LD light source has high coherence, and speckles occur when used as illumination. However, the light output from PC-0pl shown in Fig. 29 is a set of many beams with different optical paths, and the coherence is It has been eased.

 Note that a polarizing element such as a 1 Z 2 wavelength plate, a birefringence crystal walk-off polarization separating element, or a depolarizer may be inserted between the mirror 2902 and the reflective polarization separating element 2908. It is also effective to use a laser diode (L D) or LED as the light source.

 Example 4

 [0194] A light absorber and a photoelectric conversion device according to Example 4 of the present invention will be described in detail with reference to the drawings. The present embodiment is a light absorber and photoelectric conversion device using H-type propagation.

[0195] A general photoelectric conversion device uses the photovoltaic effect of a semiconductor (separated into electrons and holes when the semiconductor absorbs light) as its basic operation principle (non-patent document) (See item 7).

 [0196] In general, a photoelectric conversion device using a semiconductor extracts a carrier by using a semiconductor junction. Semiconductor light absorption processes are broadly divided into interband absorption, band-localized level absorption, localized level-level absorption, and intraband absorption. An area is generated. Localized interlevel absorption and in-band absorption are not involved in free carrier generation, and absorbed photon energy is converted into thermal energy.

 [0197] There is a loss in the energy conversion of the photoelectric conversion device. This loss is due to the first loss due to the fact that the phone does not reach 100% of the free carrier generation unit, the second loss due to the fact that the free carrier generation unit cannot absorb 100% of the photons, the free carrier generation unit The photons absorbed by can not be converted into 100% electrical energy, and it is divided into the third loss and the fourth electrical loss.

 [0198] In light absorbers (layers) used in photoelectric conversion devices, particularly solar cells, a thick light absorption layer is necessary to improve the light absorption efficiency. Conversely, a thick light absorption layer was used. In some cases, there was a dilemma in which the recombination of electrons and holes resulted in a low conversion efficiency to electrical energy.

 [0199] On the other hand, when a plane wave is incident on an arbitrary position in the thin film optical element as shown in H type propagation (A) and (B) perpendicular to the surface or in an arbitrary angular range, the optical element Since light can be propagated in-plane, a single light absorber (film) with a low light absorptance can absorb a large amount of light, eliminating the dilemma. The constituent medium of the periodic structure used at that time needs to contain a fluid such as a semiconductor, a transparent conductor, or an electrolytic solution.

Based on the above, the photoelectric conversion device according to Example 4 will be described in detail with reference to the drawings. Figure 30 is a schematic side view of a photoelectric conversion device based on “2D-collapsed ACPC” consisting of amorphous SiC (hereinafter “aS i C”) and thin-film polycrystalline silicon (hereinafter “rcSi”). It is. As shown in FIG. 30, the photoelectric conversion device comprises a glass substrate and a glass substrate on which a Si 0 ₂ barrier layer (not shown), a back electrode 3001 that also serves as a mirror, and a transparent conductive film (TCO) made of ITO. 3002, “2D-collapsed ACPC” 3003, transparent conductive film 3004, electrodes 3005 and 3006, and SiO ₂ layer 3007. Basic structure Pi-nZp-i-nZ ■ ■ ■ Zp-in two-terminal connection stack type.

[0201] The features of the present embodiment are mainly the following three points.

 (1) Use Ph C “2D-collapse ACPC” which has conductivity in the Z direction and shows H-type propagation (A), (B) and (C).

 (2) Light incident from outside propagates while being confined inside PhC by H-type propagation (A), (B), and (C), and is absorbed, thereby absorbing light compared to bulk materials. Increase efficiency.

 (3) As described above, the light absorptivity derived from the electron band structure is compensated by controlling the photon band structure and the light propagation direction.

 [0202] Specifically, by allowing the light incident perpendicularly to the surface (incident in the _Z direction) to propagate in the in-plane X direction, the photons are efficiently absorbed and the carriers are extracted in the soil Z direction. Thus, a thinner light absorption layer enables sufficient light absorption and suppresses recombination loss of electrons and holes. In addition, the energy of photons having a wavelength longer than the absorption edge can be used (free carriers generated by absorption between bands and localized levels can be extracted).

 [0203] Figure 31 shows the PrC and BAS of "2D-collapse ACPC" 3003 shown in Figure 30. Figure

 31 (a) is P r C, the length of the first PT V3101 parallel to the X direction is 350 nm, the length of the second PTV3102 is 161 nm, and has an angle of 86 degrees with respect to the XY plane. , And parallel to the ΖΧ plane, the third P TV is uniform in the Υ direction, and the length cannot be uniquely defined (optional). Reference numerals 3103 to 3106 denote lattice points. Fig. 31 (b) is a BAS, parallel to the plane containing the first PT V3101 and the second PT V3102 (here parallel to the ZX plane) and including the midpoint of the third P TV It is sectional drawing by a surface.

[0204] The BAS in Fig. 31 (b) consists of regions 3107 and 3108 occupied by i-type // c-Si, region 3109 occupied by n-type // cSi, and region 3110 occupied by | 3-type 3-3 ^, 3111 and 3112. The region 3107 and the region 3108 are continuous as a periodic structure. The same applies to the regions 3110, 3111 and 3112. In terms of the refractive index distribution, the regions 3107 and 3108 and the region 3109 can be regarded as one body. The thickness of the i-type // c-Si layer is about 100nm, the thickness of the n-type // c-Si layer is About 10 nm, the thickness of the p-type a-SiC layer is about 50 nm.

Next, the medium used will be described. “A-SiC” is a p-type semiconductor with E g = 2.0 to 2.leV and _n = 2. ■ l (at a wavelength longer than the absorption edge). On the other hand, // c-Si is E g½1.1 eV _n ½3.4 (at a wavelength longer than the absorption edge). The “c-Si” layer is divided into a non-doped layer and an n-type semiconductor layer, but the refractive index is the same, and can be regarded as one when considering the behavior of photons as P h C.

 [0206] In this example, // c-Si was used as the high refractive index medium in P h C, but any medium with n = 3 can be substituted. For example, it is also effective to use a-SH instead of // c-Si. “AS H” has a higher light absorption rate in the visible region than c-Si, but is inferior in electrical characteristics (carrier transport characteristics) and has a minority carrier diffusion length of 100 nm or less (Non-patent Document 7) See). However, in Pr C and BAS, which are light absorbers from visible light using aS H with P h C, the thickness of the aS i: H layer can be 100 nm or less, so photoelectric conversion with P h C In the device, while suppressing the problems of aSH, it is possible to use the advantages (large bottom absorption on the longer wavelength side than the absorption edge, large band gap energy, etc.). Examples of materials that satisfy n≥3 in the transparent wavelength band include semiconductors such as Si, Ge, SiGe, gallium arsenide, and aluminum gallium arsenide compounds.

 [0207] The material of the ideal light absorption layer (i layer) in this example is described as follows.

 (1) The band gap energy of electrons is large.

 (2) As the absorption coefficient becomes longer than the absorption edge, the absorption coefficient does not decrease suddenly but decreases gently (absorptive absorption is large. Band ■ there is absorption between localized levels).

 (3) Refractive index is large (n≥3)

 (4) Low resistivity.

 (5) Electrical bonding is possible with the p-type transparent conductive film.

[0208] Next, the window layer (a layer that does not absorb photon and has electrical conductivity) will be described. “A-SiC” is a wide-bandgap semiconductor and has a solar spectrum. Light absorption in the region is small and suitable for use as a window layer in a photoelectric conversion device for sunlight, but a-SiO can be used instead of a-SiC (see Non-Patent Document 7).

Next, the overall configuration of the present embodiment will be described. First, the white plate glass 5 mm thick flat plate, forming a barrier layer of Si0 _2, to form a metal electrode thereon. Furthermore, about 500 nm of ITO is laminated on it by sputtering. Next, patterning is performed on the I TO layer using a photosensitive resist film and mask exposure, and a relief type unevenness is formed by etching. After that, a triangular shaped layer of ITO is laminated by bias sputtering. Next, the following steps (1) to (3) are repeated for one cycle or more.

[0210] (1) 10 nm of a-Si is deposited by sputter deposition, polycrystallized by annealing with an excimer laser, and then doped with impurities by ion implantation and lamp annealing to form n-type // C- Si is formed. In addition, impurity doping to the n layer can be performed by using argon, hydrogen, PH ₃ mixed gas at the time of film formation by rf sputtering, or a target to which the impurity is added can be used.

 [0211] (2) Laminate 100nm of a-Si by sputtering deposition and anneal with an excimer laser to polycrystallize.

[0212] (3) A-SiC is formed according to the self-cloning method described above. “A-SiC” is formed by rf bias sputtering of a SiC target with argon and C ₂ H ₂ . Another method can be obtained by rf sputtering of Si target with argon and C ₂ H ₂ (reactive sputtering). In addition, SiC is doped with aluminum as an impurity to make a p-type semiconductor.

[0213] Finally, an ITO layer is formed by bias sputtering under the condition for filling the irregularities (increasing the bias amount). The structure shown in FIG. 30 is completed by forming a comb-shaped metal electrode on this ITO layer. Further, it is also effective to form a Si 0 ₂ film as an antireflection layer by an arbitrary film forming method. In this example, a “2D-collapsed ACPC” layer is formed by rf sputtering. This can also be realized by a combination of a sputtering method, a CVD method and etching.

[0214] In this example, light is incident from the p layer side because the hole transport property is inferior to the electron transport property, and it is more advantageous to enter light from the p layer side. Yes (see Non-Patent Document 7). In addition, one of the // cSi layers in this example is thinner than the film thickness (100 m or more) of a thin film multilayer solar cell using normal // cSi at 100 nm, but the light is // cS. It is desirable that light absorption be performed near the junction because the generation of electron-hole pairs is particularly strongly absorbed near the surface of i, and the electron-hole pairs are separated and moved to the junction. As shown in the example, the thinness of one // cSi layer is advantageous for higher efficiency. In this embodiment, “2D-collapse ACPC” is used. However, if “3D-collapse ACPC” is used, light can be efficiently absorbed in a wider wavelength band.

[0215] Next, P r C and BAS in the P h C part will be supplemented. In the P h C part in the photoelectric conversion device of Fig. 30, a configuration in which the distribution of n is almost the same and electrically different is possible. The high refractive index portion is P-type aS H, i-type aS H, a multilayer film by n-type aS H, be a low refractive index portion is Sn0 ₂ of P r C and BAS, the photonic band structure is almost identical As shown in FIG. 30, an excellent photoelectric conversion device can be realized because electrical connection is made.

[0216] Further, it is effective to use a Sn0 ₂ or ZnO instead of ITO.

[0217] Furthermore, in this example, one type of periodic structure consisting of P r C and BAS was used, but as described in the solution section, multiple periodic structures of different P r C and BAS are connected in the Z direction. By doing so, it is possible to efficiently carry out photoelectric conversion by propagating incident light at a wider wavelength within the thin film surface. For different PrC and BAS, change the film thickness when the length of the basic lattice vector is different, and change the incident direction of the deposited particles or etching particles when the direction of the basic lattice vector is different. It is feasible. In addition, BAS with a different refractive index distribution can be realized by changing the deposited particles and dopant. In particular, it is effective to change the deposited particles in the i layer, and the effect equivalent to the stack type in conventional solar cells can be obtained. [0218] In order to minimize light shielding by the electrodes, it is effective to add a prismatic cover (see Non-Patent Document 7) outside. Prismatic force If the refractive index of the bar is small, light leaking from the periodic structure 3003 to the prismatic cover is sufficiently small.

 Example 5

 [0219] A periodic structure using a fluid in part according to Example 16 of the present invention will be described in detail with reference to the drawings. This example is a periodic structure corresponding to the first to tenth inventions other than AC-PhC.

[0220] FIG. 32 is T i 0 _2, Sn0 _2, Ru sectional view der 3D P h C prepared by using iodine solution. Reference numeral 3201 represents T i 0 ₂ , reference numeral 3202 represents Sn0 ₂ , reference numeral 3203 represents an iodine solution, and reference numeral 3204 represents a substrate. The PTV of the periodic structure is in the direction inclined by 86 degrees with respect to the X, Y, and XY planes.

[0221] A feature of the present embodiment is that a fluid is used as one of the media, and the fluid can be exchanged with the outside. Examples of liquid optical devices include wet solar cells, but if an electrolyte, especially iodine solution, is used as the liquid and an electrode is connected to the outside, the periodic structure shown in Fig. 32 is also used as a wet color solar cell. Operate. The manufacturing how, Sn0 after forming the ₂ and T i 0 ₂ of the multilayer film to form a Luke or grooves drilled capable of injecting a fluid (see Patent Document 6).

 [0222] When one of the media is a fluid as in this embodiment, there are advantages that the propagation characteristics can be made variable and that a chemical reaction can be generated inside the periodic structure. Will be described. Also in this embodiment, light incident from the Z direction propagates in the X direction within the periodic structure. Propagation in the X direction is equivalent to confining light in the periodic structure, resulting in a wet solar cell with high conversion efficiency. Industrial applicability

[0223] The present invention can be suitably used in the field of optical operations such as optical branching, spectroscopy, and optical recording.

Claims

The scope of the claims  [1] A periodic structure composed of two or more types of media having a refractive index greater than 1.2, and there is a combination in which the ratio of the refractive index between the contained media is greater than 1: 1.2. Of the first to third basic translation vectors constituting the lattice, includes any axis orthogonal to the plane containing the first and second basic translation vectors, and is parallel to the first basic translation vector The distribution of the dielectric constant or refractive index in the unit structure and the Z or basic unit scale are non-mirror-symmetric with respect to the plane and the plane parallel to the Z or second basic translation vector, A periodic structure whose refractive index or dielectric constant changes periodically.  [2] A periodic structure composed of two or more types of media having a refractive index greater than 1.2, and there is a combination in which the ratio of the refractive index between the contained media is greater than 1: 1.2. 1st and 2nd of the first to third basic translation vectors constituting the basic unit cell, where the distribution of dielectric constant or refractive index and Z or the basic unit cell are non-rotation symmetric and non-inversion symmetric. Non-mirror-symmetric with respect to a plane that contains any axis orthogonal to the plane containing the primary translation vector and parallel to the first basic translation vector and the plane parallel to the Z or second basic translation vector A periodic structure having a refractive index or a dielectric constant that periodically changes.  [3] Periodic structures composed of two or more types of media having a refractive index greater than 1.2, and there are combinations in which the ratio of the refractive index between the contained media is greater than 1: 1.2. A periodic structure in which a refractive index or a dielectric constant changes periodically, characterized in that a dielectric constant or refractive index distribution therein and Z or a basic unit cell have only translational symmetry.  [4] The periodic structure according to any one of [1] to [3], wherein the second basic translation vector can have any length that is not zero. [5] The angle between the plane containing any two of the first to third basic translation vectors and the remaining one of the basic translation vectors is greater than 60 degrees <90 degrees The periodic structure according to claim 1, wherein the periodic structure is smaller. [6] The periodic structure is formed by laminating a plurality of thin films, the thin film layer has a periodic uneven structure, and the protrusions in the uneven structure have a plurality of distances from the top to the bottom. The periodic structure according to claim 1, wherein the periodic structure is a convex portion.  [7] The length of at least one basic translation vector is from 100 nm to 100 nm, and at least one of the media included in the unit structure has a refractive index of 2 or more. The periodic structure according to any one of claims 1 to 6.  [8] A plane containing any axis perpendicular to the plane containing the first and second basic translation vectors, parallel to the first basic translation vector, and the Z or second basic translation vector The periodic structure according to claim 1, wherein the electromagnetic field exhibits a non-mirror-symmetric eigenmode with respect to a plane parallel to the surface.  [9] The electromagnetic field includes any axis perpendicular to the plane containing the first and second basic translation vectors, and a plane parallel to the first basic translation vector and the Z or second basic translation vector. The periodic structure according to any one of claims 1 to 7, wherein the periodic structure is non-mirror-symmetric with respect to a plane parallel to the axis and exhibits an eigenmode that is non-rotational symmetric with respect to the axis. body.  [10] Regardless of the direction of excitation, the electromagnetic field contains any axis perpendicular to the plane containing the first and second basic translation vectors, and the plane parallel to the first basic translation vector and Z Or non-mirror symmetry with respect to a plane parallel to the second basic translation vector, and having an eigenmode having no rotational symmetry of 3 or more times with respect to the axis, The periodic structure according to claim 1.  [1 1] An electromagnetic wave beam incident at a predetermined angle on a plane including any two of the first to third basic translation vectors is propagated in a direction parallel to the plane. Or the periodic structure according to any one of claims 1 to 10, wherein the periodic structure is propagated with respect to the surface at an angle greater than a critical angle between the periodic structure and air. [12] Characterized by splitting incident beam into multiple beams propagating parallel to each other The periodic structure according to any one of claims 1 to 11. [13] The beam propagation direction according to claim 11 or the beam branch direction according to claim 12 is the direction of the first or second basic translation vector or the first to third directions. 1. The periodic structure according to claim 1, wherein the periodic structure is a direction in which one basic translation vector remaining on a surface including any two basic translation vectors is projected. body. [14] The intensity ratio of the two beams propagating in the in-plane opposite directions in claim 11 by changing the incident angle or position of the incident beam or the wavelength of the incident beam, or the same direction in claim 1 2 The periodic structure according to any one of claims 11 to 13, wherein at least one of an intensity ratio of a beam propagating to the beam and a branching interval changes. [15] Compared to the periodic structure according to any one of claims 1 to 7, the basic unit cell has the same cross-sectional area or volume, and each of the basic translational vectors contained therein has the same unit structure. The medium type and the composition ratio in the medium are the same, and the center value of the energy corresponding to the wavelength of the opposite mode of the mirror-symmetric basic unit lattice and the periodic structure of the unit structure is ± 3 O o / A periodic structure in which a refractive index or a dielectric constant periodically changes, which exhibits the beam propagation form according to any one of claims 11 to 14 at a wavelength corresponding to o.  [16] The periodic structure according to any one of [1] to [15], wherein a pn junction or a pin junction exists in a medium in the unit structure of the periodic structure.  [17] The periodic structure according to any one of [1] to [16], wherein the medium in the periodic structure includes a transparent conductive material, and the periodic structure has electrical conductivity. body.  [18] The periodic structure according to any one of claims 1 to 17, wherein the medium in the periodic structure includes a fluid and a solid. [19] The period according to any one of [1] to [18], wherein a part of the medium in the unit structure contains either a nonlinear optical material or a luminescent substance. Structure.  [20] The periodic structure according to any one of claims 1 to 19, and another periodic structure connected to the periodic structure and continuous with the periodic structure and a medium,  The sum of the first to third basic translation vectors constituting the periodic structure is different from the sum of the first to third basic translation vectors constituting the other periodic structure. A complex periodic structure.  [21] A composite periodic structure comprising the periodic structure according to any one of claims 1 to 19 and a uniform medium connected to the periodic structure.  [22] A periodic structure manufactured by using at least one of anisotropic deposition and anisotropic etching on a substrate having an uneven shape formed with a one-dimensional periodicity or a two-dimensional periodicity. A manufacturing method of  The average incident direction of deposited particles or etched particles to the substrate is not perpendicular to the substrate surface,  The angle formed by the direction in which the incident direction is projected onto the substrate surface and the direction of the periodicity is in a range of 0 to 45 degrees,  The manufacturing method of the periodic structure in any one of Claim 1 to 7.  [23] The periodic structure or composite periodic structure according to any one of claims 1 to 21, a light source, a polarizer, a reflective polarization separation element, a walk-off polarization separation element, a reflection means, a phase plate, A device having at least one selected from the group consisting of a diffraction grating, a scatterer, a spatial light modulator, an electrode, a photoconductor, and a light receiver.  [24] A parallel beam source, the periodic structure according to any one of claims 11 to 14, and a reflective polarization separation element,  A plane including any two of the first to third basic translation vectors in the periodic structure and the reflective polarization separation element are parallel to each other; The device according to claim 1, wherein a beam from the parallel beam source is incident on the periodic structure a plurality of times by the reflective polarization separation element. A laser light source, a spatial light modulator, a lens, a photoconductor, and the periodic structure according to claim 12,  By the periodic structure, the beam incident from the laser light source is branched into a plurality of beams propagating in the same direction as the incident light and in parallel with each other, and among the plurality of beams branched by the spatial light modulator Transmit or reflect at least one beam,  The device, wherein the plurality of beams including at least a beam transmitted or reflected by the spatial light modulator are collected by the lens at the same location on the photoconductor.