CN117471578A - Multifunctional layered structure metamaterial optical element and preparation method thereof - Google Patents
Multifunctional layered structure metamaterial optical element and preparation method thereof Download PDFInfo
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- CN117471578A CN117471578A CN202311396039.5A CN202311396039A CN117471578A CN 117471578 A CN117471578 A CN 117471578A CN 202311396039 A CN202311396039 A CN 202311396039A CN 117471578 A CN117471578 A CN 117471578A
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- 230000003287 optical effect Effects 0.000 title claims abstract description 57
- 238000002360 preparation method Methods 0.000 title abstract description 9
- 230000010287 polarization Effects 0.000 claims abstract description 6
- 239000010410 layer Substances 0.000 claims description 77
- 230000000737 periodic effect Effects 0.000 claims description 31
- 239000000463 material Substances 0.000 claims description 12
- 239000000126 substance Substances 0.000 claims description 11
- 238000003801 milling Methods 0.000 claims description 7
- 239000000758 substrate Substances 0.000 claims description 7
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 6
- 238000000034 method Methods 0.000 claims description 6
- 239000000470 constituent Substances 0.000 claims description 5
- GRTOGORTSDXSFK-XJTZBENFSA-N ajmalicine Chemical compound C1=CC=C2C(CCN3C[C@@H]4[C@H](C)OC=C([C@H]4C[C@H]33)C(=O)OC)=C3NC2=C1 GRTOGORTSDXSFK-XJTZBENFSA-N 0.000 claims description 4
- 238000000354 decomposition reaction Methods 0.000 claims description 3
- 238000000151 deposition Methods 0.000 claims description 3
- 230000008021 deposition Effects 0.000 claims description 3
- 238000000231 atomic layer deposition Methods 0.000 claims description 2
- 239000002131 composite material Substances 0.000 claims description 2
- 238000010884 ion-beam technique Methods 0.000 claims description 2
- 230000008569 process Effects 0.000 claims description 2
- 239000002356 single layer Substances 0.000 claims description 2
- 230000000149 penetrating effect Effects 0.000 claims 1
- 230000010354 integration Effects 0.000 abstract description 3
- 238000002834 transmittance Methods 0.000 description 6
- 230000008033 biological extinction Effects 0.000 description 5
- 238000004364 calculation method Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000004088 simulation Methods 0.000 description 3
- 230000004075 alteration Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000005445 natural material Substances 0.000 description 2
- 229910002601 GaN Inorganic materials 0.000 description 1
- JMASRVWKEDWRBT-UHFFFAOYSA-N Gallium nitride Chemical compound [Ga]#N JMASRVWKEDWRBT-UHFFFAOYSA-N 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 239000010408 film Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 238000000411 transmission spectrum Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
- G02B1/002—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of materials engineered to provide properties not available in nature, e.g. metamaterials
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/08—Mirrors
- G02B5/0816—Multilayer mirrors, i.e. having two or more reflecting layers
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3083—Birefringent or phase retarding elements
Abstract
The invention discloses a multifunctional layered structure metamaterial optical element and a preparation method thereof. The multifunctional metamaterial element provided by the invention is formed by alternately stacking a plurality of dielectric layers with different dielectric constants; the thickness of each layer in the direction perpendicular to the layer plane is less than one tenth of the operating wavelength. According to the theory of effective medium and theory of perfect matching layer, the electromagnetic wave with specific frequency, incidence direction and polarization state can show the functions of reflector, half wave plate, quarter wave plate and polarizer when it is irradiated to the layered structure. The layered structure functional optical element has the advantages of multiple functions, small volume, easy preparation and integration and the like.
Description
Technical Field
The invention relates to the technical field of optical elements and preparation thereof, in particular to a multifunctional layered structure metamaterial optical element and a preparation method thereof.
Background
In the past ten years, the multifunctional optical component has great application value in the fields of optical communication, optical remote sensing and liquid crystal display, and attracts wide research interests. However, most of the natural substances have optically isotropic or weakly anisotropic properties, resulting in a single optical property. The optical element constructed by most of natural substances at present has the problems of large volume and single function, and cannot meet the demands of people on compact structure, excellent performance and functional integration of the optical element. For example, conventional natural birefringent crystals, dichroic thin film polarizers, the former are bulky, expensive, the latter have limited polarization properties, and the process of both MEMs is complex and not easy to integrate. For this reason, achieving multi-functional integration of optical elements remains a major challenge to be addressed.
Disclosure of Invention
In view of the foregoing, it is desirable to provide a compact, superior performance, easy to integrate, and multifunctional optical element that addresses the shortcomings of the prior art.
In order to achieve the above purpose, the present invention adopts the following technical scheme: a multifunctional layered structure metamaterial optical element comprises a structure formed by alternately stacking a plurality of layers with different dielectric constants, wherein the thickness of each layer in the direction perpendicular to a layer surface is smaller than one tenth of the working wavelength, and working electromagnetic waves are incident to the layered structure optical element in the direction perpendicular to the layer surface or in the direction parallel to the layer surface.
When the incident electromagnetic wave direction is perpendicular to the incident layered structure metamaterial, the incident electromagnetic wave can be decomposed into reflected electromagnetic wave and transmitted electromagnetic wave at the middle interface of two adjacent layers of substances, and the transmitted electromagnetic wave is further decomposed into the reflected electromagnetic wave and the transmitted electromagnetic wave at the next interface in the propagation direction; by analogy, by combining electromagnetic wave interference effect, as long as reasonable structural parameters are designed, the incident electromagnetic wave is subjected to repeated reflection or decomposition, and finally the electromagnetic wave transmitted through the layered structure material is approaching to 0, namely almost all the incident electromagnetic wave converts the reflected electromagnetic wave, thereby realizing the function of a reflector. In order to maximize the operating bandwidth and performance of the reflector, the length of the optical element in the vertical plane direction is required to be 2.80 to 3.01 times the operating wavelength. In addition, in order to integrate the functions of the half wave plate, the quarter wave plate and the polarizer at the same time and optimize the performance of the element, the invention combines the theory of perfect matching layers, and through calculation and deduction, the ratio of the width of the cuboid layered structure in the direction of one parallel layer to the ratio of the height of the other parallel layer to the working wavelength is required to be in the range of 0.38-0.43 and 0.19-0.23 respectively.
Further, the monolayer thickness of the multilayer film structure is less than one tenth of the operating wavelength.
Further, the working electromagnetic wave is perpendicular or parallel to the layer direction and is incident perpendicular to the element surface.
Further, the electromagnetic wave is linearly polarized, circularly polarized or elliptically polarized, and the wave band of the electromagnetic wave covers visible light, infrared light and terahertz waves.
Further, the periodic unit structure is characterized by being a composite layer formed by alternately stacking three or more layers with different dielectric constants.
Further, the constituent materials of the periodic unit structure are all media.
Further, preparing a first layer of substance I by epitaxial growth on a substrate by utilizing an atomic layer deposition method, and then growing a second layer of substance II on the first layer; and so on, the growth of one periodic unit structure is completed.
Specifically, more than 30 deposition cycles are performed during the growth of each layer of material, and then the layer is milled and the next layer is grown on the milled surface.
Specifically, after one periodic unit structure growth is completed by using molecular beam growth, the 2 nd periodic unit structure growth is completed on the periodic unit structure; and the like, the growth of the whole lamellar structure is completed.
Specifically, after the epitaxial growth prepares a periodic unit structure, the method further comprises: milling the last layer.
Specifically, after all periodic layers are grown, the substrate is peeled off with acetone, and the surface of the laminated structure after the substrate is peeled off is milled by using a focused ion beam.
Compared with the traditional multifunctional optical element, the multifunctional layered structure metamaterial optical element has the advantages of simple structure, mature manufacturing process technology, easiness in batch and standardized preparation, capability of generating strong interaction with electromagnetic waves in different frequency bands, and capability of displaying different optical properties, anisotropism and the like.
In the preparation method provided by the invention, more than 30 deposition cycles are needed when each layer of substance is prepared, and after all periodic layers are grown, the substrate is stripped by acetone, so that the uniformity of the structure of each layer of substance is facilitated, the milling error is reduced, and the device reflection performance is improved while the stability and the yield of the device are improved.
The invention adopts the technical proposal has the advantages that: the multifunctional layered structure metamaterial optical element provided by the invention utilizes electromagnetic wave interference effect, effective medium theory, perfect matching layer theory and mature stratum material processing technology, effectively integrates and improves functions and performances of a reflector, a half wave plate, a quarter wave plate and a polarizer, simultaneously greatly simplifies design, processing and manufacturing of the traditional multifunctional optical element, and obtains the multifunctional optical element with more compact structure and more excellent performance.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic structural diagram of a multifunctional layered structure metamaterial optical element provided by an embodiment of the present invention;
FIG. 2 is a graph showing the transmittance spectrum of an incident light perpendicular to the plane (along the x-axis) when the incident light is incident on the multifunctional element according to an embodiment of the present invention;
fig. 3 shows the transmittance and ellipticity of an embodiment of the present invention when incident light is incident on the multifunction element parallel to the layer plane and perpendicular to the element surface (along the y-axis).
FIG. 4 shows ellipticity and extinction ratio of incident light upon the multifunction element parallel to the plane of the layer and perpendicular to the surface of the element (along the z-axis) as provided by an embodiment of the invention.
In the figure, 1 is an electromagnetic wave incident in the x-axis direction, 2 is an electromagnetic wave incident in the y-axis direction, 3 is an electromagnetic wave incident in the z-axis direction, 4 is a periodic cell structure constructed of three layers of substances, 5 is a layer I in the periodic cell structure, 6 is a layer II in the periodic cell structure, 7 is a layer III in the periodic cell structure, x 1 Is the thickness of layer I, x 2 Is the thickness of layer II, x 3 Is the thickness of layer III, l is the length of the multifunctional element, w is the width of the multifunctional element, h is the height of the multifunctional element, T x T for transmittance of incident electromagnetic wave along x-axis direction y And EP y The transmittance and ellipticity of the electromagnetic wave after the incident electromagnetic wave passes through the multifunctional element along the y-axis direction are respectively, EP z And EXT z The ellipticity and extinction ratio of the electromagnetic wave after the electromagnetic wave is incident along the z-axis direction and transmitted through the multifunctional element are respectively.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In order to better understand the above technical solutions, the following detailed description will refer to the accompanying drawings and specific embodiments.
The schematic structural diagram of the layered multifunctional optical element provided by the embodiment of the invention is shown in fig. 1. The periodic unit structure of the multifunctional optical element is composed of a layer I, a layer II and a layer III. The thicknesses of the layer I, the layer II and the layer III are respectively 1 micron, 1 micron and 2 microns, and the constituent substances are respectively silicon, gallium nitride and silicon oxide; the number of periodic cell structures was 20. The multifunctional optical element has a length l=80 micrometers in the x-axis direction, a width w=10 micrometers in the y-axis direction, and a height h=5 micrometers in the z-axis direction.
When an input electromagnetic wave 1 is incident on the multifunctional optical element along the vertical layer direction (x-axis direction), the incident electromagnetic wave is decomposed into a reflected electromagnetic wave and a transmitted electromagnetic wave at the middle interface of two adjacent layers of substances, and the transmitted electromagnetic wave is further decomposed into a reflected electromagnetic wave and a transmitted electromagnetic wave at the next interface in the propagation direction; by analogy, by combining electromagnetic wave interference effect, as long as reasonable structural parameters are designed, the incident electromagnetic wave is subjected to repeated reflection or decomposition, and finally the electromagnetic wave transmitted through the layered structure material is approaching to 0, namely almost all the incident electromagnetic wave converts the reflected electromagnetic wave, thereby realizing the function of a reflector. The results are shown in fig. 2 after simulation calculation. The transmittance of electromagnetic waves is close to 1 in the wavelength range of 26.5-28.5 microns.
When the input electromagnetic wave 2 is incident to the multifunctional optical element along the parallel layer direction (y-axis direction), the dielectric constants of the multifunctional optical element in the vertical layer direction and the parallel layer direction are different according to the effective medium theory, and the functions of the half wave plate can be realized simultaneously by reasonably designing the width of the multifunctional optical element in the y-axis direction on the basis of the perfect matching layer theory and the requirement of the half wave plate on the optical property of the material. The results are shown in fig. 3 after simulation calculation. In the wavelength range of 23.1-26.1 microns, the transmittance of polarized electromagnetic waves perpendicular to the incident polarization direction is 0.7-0.8 and the ellipticity is close to 0.
When the input electromagnetic wave 3 is incident to the multifunctional optical element along the parallel layer direction (z-axis direction), according to the effective medium theory, the dielectric constants of the multifunctional optical element in the vertical layer direction and the parallel layer direction are different, and the perfect matching layer theory and the requirements of the quarter wave plate and the polarizer on the optical properties of materials are combined, so that the functions of the quarter wave plate and the polarizer can be further and simultaneously realized by reasonably designing the height of the multifunctional optical element in the z-axis direction on the basis of the perfect matching layer theory. The results are shown in fig. 4 after simulation calculation. In the wavelength range of 20.0-21.4 microns, the ellipticity of the transmitted electromagnetic wave is close to 1; the extinction ratio is in the range of 30dB to 42dB in the wavelength range of 24.6 to 26.1 microns.
In some preferred examples, the reflector operating bandwidth of the multifunction optical element widens as the number of periodic layers increases.
In some preferred examples, the working electromagnetic waves incident along the x-axis may be linearly polarized, circularly polarized, and elliptically polarized electromagnetic waves.
In some preferred examples, the wave band of the working electromagnetic wave covers visible light, infrared light and terahertz waves by adjusting the structural shape parameters of the multifunctional optical element in equal proportion and selecting proper constituent substances.
In some preferred examples, the extinction ratio of the polarizer of the multifunction optical element increases as the number of periodic layers increases.
It will be appreciated that the operating wavelength, transmittance, ellipticity, extinction ratio, etc. parameters of the reflectors, half wave plates, quarter wave plates and polarizers of the multifunction optical element may be adjusted according to the constituent materials and volume ratios of the layers in the periodic structure.
From the above description, it should be clear to a person skilled in the art that the multifunctional layered structure metamaterial optical element provided by the embodiments of the present invention.
The embodiment of the invention provides a preparation method of a transmission polarizer, which comprises the following steps: firstly preparing a first layer of substance I by epitaxial growth, milling the layer, and growing a second layer of substance II on the milling surface; milling the layer after the second layer of substance II grows, and growing a third layer of substance III on the milling surface; and so on, the growth of one periodic unit structure is completed. After the growth of one periodic unit structure is completed by utilizing the molecular beam growth, the growth of the 2 nd periodic unit structure is completed on the periodic unit structure; and the like, the growth of the whole lamellar structure is completed.
In summary, the multifunctional layered structure metamaterial optical element provided by the invention utilizes electromagnetic wave interference effect, effective medium theory, perfect matching layer theory and mature stratum material processing technology, and greatly simplifies the design, processing and manufacturing of the traditional multifunctional optical element while effectively integrating and improving the functions and performances of the reflector, the half wave plate, the quarter wave plate and the polarizer, so that the multifunctional optical element with more compact structure and more excellent performance is obtained.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
Claims (10)
1. The multifunctional laminated metamaterial optical element is characterized by comprising a periodic unit structure formed by alternately stacking a plurality of dielectric layers with different dielectric constants, wherein the periodic unit structure forms a cuboid optical element. The length of the optical element in the vertical layer direction is 2.80-3.01 times of the working wavelength, and the ratio of the width in one parallel layer direction to the height in the other parallel layer direction to the working wavelength is respectively in the range of 0.38-0.43 and 0.19-0.23. When working electromagnetic waves are incident in the direction perpendicular to the layer surface, the electromagnetic waves are subjected to multiple reflection or decomposition, and finally the electromagnetic waves penetrating through the layered structure material are close to 0, namely almost all the incident electromagnetic waves are converted into reflected electromagnetic waves, so that the function of a reflector is realized; when working electromagnetic waves are perpendicular to the surface of the element and are incident along the width direction of the parallel layer, the optical element has the function of a half wave plate; when working electromagnetic waves are vertical to the surface of the element and are incident along the height direction of the parallel layers, the optical element has the functions of a quarter and a polarizer.
2. The layered structure optical element of claim 1, wherein the multilayer film structure has a monolayer thickness of less than one tenth of the operating wavelength.
3. The layered structure optical element of claim 1, wherein the operating electromagnetic wave is incident perpendicular to or parallel to the layer plane direction and perpendicular to the element surface.
4. The layered structure optical element according to claim 1, wherein the electromagnetic wave is an electromagnetic wave of linear polarization, circular polarization or elliptical polarization, and the wave band of the electromagnetic wave covers visible light, infrared light, terahertz waves.
5. The layered structure optical element of claim 1, wherein the periodic unit structure is a composite layer of three or more layers of different dielectric constants cross-stacked.
6. The layered structure optical element of claim 5, wherein the constituent materials of the periodic unit structure are each a medium.
7. The layered structure optical element of claim 1, comprising: preparing a first layer of substance I by epitaxial growth on a substrate by utilizing an atomic layer deposition method, and then growing a second layer of substance II on the first layer; and so on, the growth of one periodic unit structure is completed.
8. The layered structure optical element of claim 7, comprising: in the process of growing each layer of material, more than 30 deposition cycles are performed, then the layer is milled and the next layer is grown on the milled surface.
9. The layered structure optical element according to claim 7 and claim 8, wherein after one periodic unit structure growth is completed by molecular beam growth, the 2 nd periodic unit structure growth is completed on the periodic unit structure; and the like, the growth of the whole lamellar structure is completed.
10. The method of claim 9, wherein after all periodic layers are grown, the substrate is stripped with acetone and the surface of the substrate is stripped by milling the layered structure with a focused ion beam.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311212294X | 2023-09-19 | ||
| CN202311212294 | 2023-09-19 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117471578A true CN117471578A (en) | 2024-01-30 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202311396039.5A Pending CN117471578A (en) | 2023-09-19 | 2023-10-25 | Multifunctional layered structure metamaterial optical element and preparation method thereof |
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| CN (1) | CN117471578A (en) |
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- 2023-10-25 CN CN202311396039.5A patent/CN117471578A/en active Pending
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