Two-dimensional light path device based on hyperbolic anisotropic metamaterial

Abstract

The invention discloses a two-dimensional light path device based on a hyperbolic anisotropic metamaterial, the device comprises a substrate, two transmission channel structures and an input end structure are formed on the substrate through focused ion beam etching, and the optical axes of the two transmission channel structures and the input end structure are located in the same plane. The two transmission channel structures meet chiral symmetric distribution relative to the input end structure, the input end structure is used for providing a coupling excitation source, and the transmission channel structures are hyperbolic anisotropic metamaterial structures; and the input end structure excites the surface wave and selectively transmits the surface wave by using hyperbolic anisotropy of the transmission channel structure and the incident wave polarization effect, so that selective excitation of different transmission channel structures is realized. Therefore, routing multiplexing of information transmission can be achieved, polarization information is reserved, additional structural design is not needed, and the method has wide application and development prospects in two-dimensional optical path information multiplexing and routing functions.

Description

Technical Field

[0001] The present invention relates to a two-dimensional optical path device based on hyperbolic anisotropic metamaterials, and relates to the technical field of material photonics. Background Art

[0002] Currently, the common information transmission carrier in compact photonics systems is the surface wave mode, which effectively reduces the occupied space of the information transmission carrier in space.

[0003] However, currently, it is very difficult to manipulate the surface wave mode in compact photonics systems. Usually, additional artificial structures are required to achieve the selectivity of the surface wave mode, resulting in complex redundancy of the structure and low transmission efficiency. Therefore, how to achieve efficient information transmission and simple and effective manipulation is the focus of the scientific community and the industrial community, and has important scientific and application significance.

[0004] Existing similar technology designs are all based on isotropic materials. Due to the isotropy of the materials, the transmission does not carry polarization information, making it difficult to achieve efficient manipulation. Summary of the Invention

[0005] The present invention aims to at least solve one of the technical problems existing in the prior art. For this purpose, in view of the above problems, the object of the present invention is to provide a two-dimensional optical path device based on hyperbolic anisotropic metamaterials, which can realize functions such as multi-channel routing multiplexing, flexible manipulation methods, and polarization information-carrying transmission.

[0006] In order to achieve the above invention object, the technical solution adopted by the present invention is as follows:

[0007] The two-dimensional optical path device based on hyperbolic anisotropic metamaterials provided by the present invention includes a substrate. Two transmission channel structures and an input end structure are formed on the substrate by focused ion beam etching. The optical axes of the two transmission channel structures and the input end structure are in the same plane, and the two transmission channel structures are chirally symmetrically distributed with respect to the input end structure. Among them, the transmission channel structure is a hyperbolic anisotropic metamaterial structure, and the input end structure excites surface waves and selectively transmits surface waves by using the hyperbolic anisotropy of the transmission channel structure and the polarization effect of the incident wave, so as to realize the selective excitation of different transmission channel structures.

[0008] In some possible implementation manners, both the transmission channel structure and the input end structure are constructed on the isotropic material substrate.

[0009] In some possible implementation manners, the substrate uses a quartz substrate.

[0010] In some possible embodiments, the transmission channel structure is a two-dimensional metamaterial structure. A metal film is deposited on the quartz substrate by electron beam evaporation, and then strip structures with different periodic sizes are fabricated by focused ion beam etching to realize a hyperbolic metasurface structure equivalent to a homogeneous medium as the transmission channel structure.

[0011] In some possible embodiments, the input end structure is a two-dimensional metamaterial structure. A metal film is deposited on the quartz substrate by electron beam evaporation, and then structures that can diffract incident light with different periodic sizes are fabricated by focused ion beam etching as the input end structure.

[0012] In some possible embodiments, the input end structure adopts a grating structure or a structural defect structure. The input end structure is designed such that the wave vector direction should point from the input end structure to the direction of the transmission channel structure, and it is located in the optical axis plane of the input end structure and the two transmission channel structures on both sides.

[0013] In some possible embodiments, an output end structure is further included on the outer sides of the two transmission channel structures. The output end structure is disposed on the quartz substrate, close to one end of the transmission channel structure, and is separated from the input end structure by the transmission channel structure. The output end structure realizes decoupling the information transmitted in the transmission channel structure into free space by etching a metal nanocylinder array with the same horizontal and vertical periodic sizes on the metal film.

[0014] In some possible embodiments, each of the transmission channel structures includes two transmission interfaces. The interface between the metal film structure and air is the upper air-side interface, and the interface between the metal film structure and the quartz substrate is the lower substrate-side interface.

[0015] In some possible embodiments, the specific manner of realizing multiplexing and routing control of information channel transmission based on the spin-momentum locking principle by the interaction between the incident wave polarization and the anisotropy of the transmission channel structure is as follows:

[0016] When linearly polarized light is incident on the input end structure and diffracted light is emitted, the diffracted light simultaneously excites the upper air-side interface of one of the two groups of transmission channel structures on both sides of the input end structure to transmit right-handed circularly polarized light, and the lower substrate-side interface to transmit left-handed circularly polarized light. The upper air-side interface of the other transmission channel structure transmits left-handed circularly polarized light, and the lower substrate-side interface transmits right-handed circularly polarized light;

[0017] When right-handed circularly polarized light is incident on the input end structure and diffracted light is emitted, the diffracted light excites the two transmission interfaces of one of the transmission channel structures on one side of the input end structure. The upper air-side interface carries the right-handed polarization state of the photon, and the lower substrate-side interface carries the left-handed polarization state of the photon;

[0018] When left-handed circularly polarized light is incident on the input end structure to emit diffracted light, two transmission interfaces of the transmission channel structure on the other side of the input end structure are excited. The upper air-side interface carries the left-handed polarization state of photons, and the lower substrate-side interface carries the right-handed polarization state of photons.

[0019] Due to the above technical solutions adopted by the present invention, it has the following characteristics:

[0020] 1. Simple operation: The present invention can realize the regulation of transmission information by regulating the incident polarization at the input end structure, and can realize the selective excitation of different transmission channel structures.

[0021] 2. High structural integration: The present invention utilizes the anisotropy of the transmission channel structure to realize the regulation function, and no additional phase modulation or chiral structure design is used at the input end and the output end.

[0022] 3. Large information throughput: The information transmission carrier of the present invention is an anisotropic surface wave, which carries polarization information during the transmission process, and a group of transmission channel structures can be composed of double interfaces, providing a solution for realizing the functions of a highly integrated on-chip system.

[0023] 4. Efficient control: The hyperbolic metamaterial structure of the present invention has anisotropy. Due to the chiral symmetry of the material with respect to the input end structure, the interaction between the incident wave polarization and the material anisotropy can be effectively utilized to achieve efficient control.

[0024] In summary, the present invention can realize the routing multiplexing of information transmission and retain the polarization information, and without additional structural design, it has broad application and development prospects in the two-dimensional optical path information multiplexing and routing functions. Brief Description of the Drawings

[0025] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. Throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0026] Figure 1 is a scanning electron microscope structural schematic diagram of a two-dimensional optical path device based on a hyperbolic anisotropic metamaterial according to an embodiment of the present invention;

[0027] Figure 2 is a structural diagram of an optical far-field test system according to an embodiment of the present invention;

[0028] Figure 3 is a schematic diagram for verifying the channel routing function according to an embodiment of the present invention;

[0029] Figure 4Schematic diagram for verifying polarization information transmission according to an embodiment of the present invention. Detailed implementation manners

[0030] It should be understood that the terms used herein are for the purpose of describing specific example embodiments only and are not intended to be limiting. Unless the context clearly dictates otherwise, the singular forms "a", "an", and "the" as used herein may also include the plural forms. The terms "include", "comprise", "contain", and "have" are inclusive and thus specify the presence of the stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring them to be performed in the particular order described or illustrated, unless the order of performance is explicitly stated. It should also be understood that additional or alternative steps may be used.

[0031] Although the terms first, second, third, etc. may be used herein to describe multiple elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or section from another. Unless the context clearly indicates otherwise, terms such as "first", "second", and other numerical terms used herein do not imply an order or sequence. Thus, the first element, component, region, layer, or section discussed below may be referred to as the second element, component, region, layer, or section without departing from the teachings of the example embodiments.

[0032] For ease of description, spatial relative relationship terms may be used herein to describe the relationship of one element or feature shown in the figure to another element or feature, such as "inner", "outer", "inner side", "outer side", "below", "above", etc. Such spatial relative relationship terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure.

[0033] Since existing designs are all based on isotropic materials, the isotropy of the materials results in the transmitted wave not carrying polarization information, making it difficult to achieve efficient manipulation. The two-dimensional optical path device based on hyperbolic anisotropic metamaterials with a compact multi-channel transmission function provided by the present invention can achieve selective optical channel transmission and retain the polarization information of the incident wave based on the interaction between the hyperbolic anisotropic metamaterials and the polarization of the incident wave. It includes a substrate, on which two transmission channel structures and an input end structure are formed by focused ion beam etching. The optical axes of the two transmission channel structures and the input end structure are in the same plane, and the two transmission channel structures satisfy chiral symmetric distribution with respect to the input end structure. Among them, the input end structure is used to provide a coupling excitation source, and the transmission channel structure is a hyperbolic anisotropic metamaterial structure. The input end structure excites surface waves and selectively transmits the surface waves by using the hyperbolic anisotropy of the transmission channel structure and the polarization of the incident wave. The key to this design is that the input end excites surface waves and selectively transmits the surface waves by using the hyperbolic anisotropy and the polarization of the incident wave to achieve selective excitation of different transmission channel structures. Therefore, the present invention can retain the polarization information of the input electromagnetic wave and has the advantages of not relying on surface plasmons, not requiring complex specific pattern design, and having a compact structure design.

[0034] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present invention can be more thoroughly understood and the scope of the present invention can be fully conveyed to those skilled in the art.

[0035] As Figure 1 shown, the two-dimensional optical path device based on hyperbolic anisotropic metamaterials provided in this embodiment includes a substrate 1, on which two transmission channel structures 2 and an input end structure 3 are formed by focused ion beam etching. The optical axes of the two transmission channel structures 2 and the input end structure 3 are in the same plane, and the two transmission channel structures 2 satisfy chiral symmetric distribution with respect to the input end structure 3. Among them, the input end structure 3 is used to provide a coupling excitation source, and the transmission channel structure 2 is a hyperbolic anisotropic metamaterial structure; the input end structure 3 excites surface waves and selectively transmits the surface waves by using the hyperbolic anisotropy of the transmission channel structure 2 and the polarization of the incident wave to achieve selective excitation of different transmission channel structures 2.

[0036] In a preferred embodiment, the relationship of the dielectric constant parameters of the transmission channel structure 2 includes but is not limited to uniaxial hyperbola, etc. The transmission channel structure 2 has the characteristic that the corresponding material optical axes are symmetrically distributed along the input end structure 1. Among them, the material optical axis is the direction in which light propagates in an anisotropic material without generating birefringence, and there is a specific dielectric constant along the optical axis direction.

[0037] In a preferred embodiment, both the transmission channel structure 2 and the input end structure 3 are constructed on the isotropic material substrate 1. The dielectric constant of the material of the interface formed by the isotropic material and the transmission channel structure 2 satisfies the condition for supporting surface wave transmission.

[0038] Furthermore, the substrate 1 can be a quartz substrate.

[0039] In a preferred embodiment, both the transmission channel structure 2 and the input end structure 1 are two-dimensional metamaterial structures. The structures are distributed in the plane. A metal film such as an Ag film is deposited on the quartz substrate by electron beam evaporation, and then periodic bar structures with different sizes are fabricated by focused ion beam etching to respectively realize a hyperbolic metamaterial structure equivalent to a homogeneous medium and an input end structure 3 capable of diffracting incident light.

[0040] Furthermore, the input end structure 3 is a coupling excitation structure capable of coupling spatial electromagnetic waves into surface waves, including but not limited to gratings, structural defects such as one-dimensional line defects, two-dimensional air disks, etc.

[0041] Furthermore, the input end structure 3 is designed such that the wave vector direction should point from the input end structure 3 to the direction of the transmission channel structure 2 and is located in the optical axis plane of the input end structure 3 and the two-side transmission channel structures 2.

[0042] In a preferred embodiment, an output end structure 4 is further included. The output end structure 4 is fabricated by focused ion beam etching on the metal film for preparing the transmission channel structure 2 and the input end structure 3. The output end structure 4 is arranged on the quartz substrate, close to one end of the transmission channel structure 2, and is separated from the input end structure 3 by the transmission channel. The output end structure 4 is a two-dimensional uniformly arranged silver nanorod resonator. The surface wave transmitted by the transmission channel structure 2 excites the resonance mode of the nanorod resonator here, and then is converted into a free space transmission wave, thereby decoupling the polarized light.

[0043] In a preferred embodiment, other transmission channel structures can be arranged in the outer direction of the transmission channel structure 2 of the two-dimensional optical path device based on hyperbolic anisotropic metamaterials of the present invention, so that the transmitted information continues to be transmitted in the surface wave mode / waveguide mode. The purpose is to extend the transmission channel and guide the information transmitted by the transmission channel structure 2 into other transmission structures. Any structure can be used as long as the wave vector matching relationship condition is satisfied, and the arrangement is not fixed.

[0044] In summary, there is no other redundant structure between the transmission channel structure 2 and the input end structure 3 of the present invention, and there is no connection structure gap between them. The two-dimensional optical path device can be extended and applied in different frequency bands. By completing the design of the transmission channel structure 2 and the input end structure 3 in different frequency bands, working frequency bands including but not limited to the visible light frequency band can be realized. Under the condition of meeting the surface wave transmission condition, the period size of the transmission channel structure required for the basic function of the two-dimensional optical path device of the present invention can be increased or decreased, and the number of periods can also be increased or decreased, which is not limited herein. Under the condition of meeting the excitation wave vector condition, the overall geometric size of the input end structure 3 of the present invention can be increased or decreased, which is not limited herein. The two-dimensional optical path device of the present invention can adopt a cage system to construct a far-field test system to improve the stability of long-term operation. In the far-field test of the two-dimensional optical path device in the visible light frequency band, a polarizer can be added to the optical path receiving end of the output signal, and the result can be observed through a CCD camera.

[0045] Based on the above embodiments, the present invention also proposes a design method for a two-dimensional optical path device based on hyperbolic anisotropic metamaterials, which mainly includes two design parts:

[0046] S1. Design the transmission channel structure 2 of the hyperbolic anisotropic metamaterial.

[0047] First, a hyperbolic anisotropic metamaterial system is conventionally formed by layer-by-layer periodic stacking or columnar periodic embedding of materials with different dielectric constants;

[0048] Second, two pieces of the same hyperbolic anisotropic metamaterial are arranged symmetrically with respect to the optical axis on both sides of the spatial symmetry axis to form the transmission channel structure 2.

[0049] S2. Design the input end structure 3.

[0050] The input end structure 3 uses common gratings, structural defects, etc. to provide two in-plane wave vectors perpendicular to the symmetry axes of the two groups of transmission channel structures 2, and can excite surface waves through incident waves. The optical axes of the two transmission channel structures 2 and the input end structure 3 are located in the same plane, and the two transmission channel structures 2 satisfy chiral symmetric distribution with respect to the input end structure 3. The key to the design is to realize the coupling of the incident wave from free space into the transmission channel structure 2 and its transmission in the form of surface waves, and due to the interaction between the incident wave polarization and the anisotropy of the transmission channel structure, selective channel excitation is realized.

[0051] Further, the specific ways to realize the routing of transmitted information based on the interaction between the incident wave polarization and the anisotropy of the transmission channel structure and based on the spin-momentum locking principle include:

[0052] When linearly polarized light is incident on the input structure 3, diffracted light is emitted. The diffracted light simultaneously excites two groups of transmission channel structures 2 on both sides of the left and right input structures 3. The upper air-side interface of the transmission channel structure 2 on one side transmits right-handed circularly polarized light, and the lower substrate-side interface transmits left-handed circularly polarized light. The upper air-side interface of the transmission channel structure 2 on the other side transmits left-handed circularly polarized light, and the lower substrate-side interface transmits right-handed circularly polarized light. Among them, each transmission channel structure 2 includes two transmission interfaces. The interface between the metal film structure and air is the upper air-side interface, and the interface between the metal film structure and the quartz substrate is the lower substrate-side interface.

[0053] When right-handed circularly polarized light is incident on the input structure 3 and diffracted light is emitted, the diffracted light excites the two transmission interfaces of the transmission channel structure 2 on one side of the input structure 3 to carry information of two polarization states, which are transmitted on the upper and lower interfaces respectively. The upper air-side interface carries the right-handed polarization state of photons, and the lower substrate-side interface carries the left-handed polarization state of photons (since it is transmitted at the interface, it is not circularly polarized light and is called photon spin);

[0054] When the incident light is left-handed circularly polarized light, the two transmission interfaces of the transmission channel structure 2 on the other side of the input structure 3 are excited. The upper air-side interface carries the left-handed polarization state of photons, and the lower substrate-side interface carries the right-handed polarization state of photons; Other incident lights containing left / right-handed circular polarization states can activate the corresponding polarization state transmission channel structures, realizing simple control of multiplexing and routing of information channels in the structure.

[0055] In a preferred embodiment, an output structure 4 can be added to decouple the polarized light. Further, by adding a left-handed / right-handed circular analyzer on the substrate side in the main energy output direction, two-dimensional optical path control applications under far-field conditions can be realized. For different working frequency bands, the application migration can be achieved by redesigning the corresponding metamaterial structure system.

[0056] The following details the implementation process of the two-dimensional optical path based on hyperbolic anisotropic metamaterials proposed by the present invention through specific embodiments.

[0057] In this embodiment, the two-dimensional optical path device based on hyperbolic anisotropic metamaterials implemented by this design is analyzed, and the feasibility of multiplexing and routing functions of information channel transmission of photons is determined. This embodiment includes two parts. First, a two-dimensional optical path device based on hyperbolic anisotropic metamaterials is prepared. Second, using a basic far-field test system, the feasibility of information transmission multiplexing and routing and the characteristics of transmission polarization attributes of the prepared two-dimensional optical path device based on hyperbolic anisotropic metamaterials are confirmed.

[0058] 1. Prepare a two-dimensional optical path device based on hyperbolic anisotropic metamaterials.

[0059] In this embodiment, the two-dimensional optical path device based on hyperbolic anisotropic metamaterials is asFigure 1 As shown, an input end structure 3 and a transmission channel structure 2 are etched out by depositing a 60-nm silver film on a quartz substrate and using focused ion beam etching. As Figure 1 (b) The corresponding input end structure 3 is composed of a grating with a period of 225 nm and a duty cycle of silver: air of 1:1, which can provide an excitation wave vector perpendicular to the long direction of the grating bars. As Figure 1 (c) The corresponding transmission channel structure 2 is composed of a hyperbolic anisotropic metamaterial with a period of 80 nm arranged and a silver: air ratio of 1:1, and is arranged symmetrically about the optical axis on both sides of the input end structure 3 (because there are two hyperbolic metamaterial structures on the left and right sides of the input end structure 3, so there are two optical axes, and these two optical axes are symmetric about the input end structure 3); As Figure 1 (d) is the output end structure, which is composed of cylinders with a period of 180 nm and a diameter of 110 nm. Each structural component in the figure is clearly visible, the structure is compact without redundancy or misalignment. The output end structure 4 is a two-dimensional uniformly arranged silver nanocylinder resonator. The surface wave transmitted by the transmission channel excites the resonance mode of the nanocylinder resonator here, and then is converted into a free space transmission wave, thereby decoupling the polarized light.

[0060] 2. The most conventional far-field test scheme is adopted as the test method to test the basic functions of the two-dimensional optical path device of the present invention.

[0061] As Figure 2 shown, the test sample is the two-dimensional optical path device of the present invention, a 633-nm laser light source is the incident light, and the polarization state of the incident light can be adjusted to linearly polarized light, left-handed circularly polarized light or right-handed circularly polarized light in the labeled area A through a linear polarizer and a λ / 4 wave plate. Secondly, a 20X objective lens is used to incident from the air side to the input end structure 3 (coupling grating) of the two-dimensional optical path device, and a linear polarizer and a λ / 4 wave plate are connected in front of the CCD camera at the reflection end as an analyzer and marked as area B, and the far-field information decoupled and emitted by the sample can be observed and tested.

[0062] As Figure 3 shown in (a) and (b) respectively correspond to the observation results without an analyzer in area B after right-handed circularly polarized light or left-handed circularly polarized light with the polarization direction along the input end structure 3 is incident (the input light is circularly polarized light. Due to the different circular polarizations of the polarized light, one of the transmission channel structures is excited. After being excited, information is transmitted in the transmission channel structure. The transmitted information carries energy. Due to defects or uneven protrusions in the actual structure preparation, etc., it will cause scattering of the transmitted information. At this time, a stronger optical signal will be detected after collecting the signal in the far field. Therefore, it can be determined that one of the transmission channel structures is excited, that is, both interfaces are excited at the same time), Figure 3 and (c) corresponds to the reference diagram of the actual structure position. As Figure 3As shown in (d) and (e), by comparing the output optical image information, it is shown that the photon device has successfully realized the encoding routing function. When incident with right-handed circularly polarized light, the lower transmission channel structure 2 can be selectively excited; when incident with left-handed circularly polarized light, the upper transmission channel structure 2 can be selectively excited; therefore, this two-dimensional optical path device satisfies the transmission information routing encoding function. In addition, for linearly polarized light with the incident polarization direction along the input end structure 3 (the grating bar structure direction), such as Figure 4 In (a) and (b) of Figure 4 , the corresponding area B is a right-handed circularly polarized light or left-handed circularly polarized light analyzer, showing the imaging results of placing a right-handed analyzer or a left-handed analyzer. In addition, Figure 4 In (c) of Figure 4 corresponds to the actual structure position reference diagram. Such as Figure 4 As shown in (d) and (e), the light emerging from the decoupling end into free space carries polarization characteristics. The light output from the decoupling port satisfies that the lower transmission channel structure 2 carries right-handed circular polarization characteristics, and the upper transmission channel structure 2 carries left-handed circular polarization characteristics. This photon system has successfully realized the transmission of polarization information.

[0063] It should be noted that this embodiment proves the rationality and feasibility of this two-dimensional optical path device under existing conditions. Based on this, further design and combined applications are also feasible. In more complex integrated photon systems, using this optical path design can successfully realize information transmission multiplexing and routing control.

[0064] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and the key points of each embodiment are to illustrate the differences from other embodiments. In the description of this specification, the descriptions referring to terms such as "a preferred embodiment", "furthermore", "specifically", "in this embodiment", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of this specification. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A two-dimensional optical path device based on hyperbolic anisotropic metamaterial, characterized in that: The device includes a substrate, on which two transmission channel structures and an input end structure are formed by focused ion beam etching, the optical axes of the two transmission channel structures and the input end structure are located in the same plane, and the two transmission channel structures satisfy chiral symmetric distribution with respect to the input end structure, wherein the transmission channel structure is a hyperbolic anisotropic metamaterial structure, the input end structure excites surface waves and utilizes the hyperbolic anisotropy of the transmission channel structure and the polarization of the incident wave to selectively transmit the surface waves, thereby realizing selective excitation of different transmission channel structures.

2. The two-dimensional optical path device based on hyperbolic anisotropic metamaterial according to claim 1, characterized in that: The transmission channel structure and the input end structure are both constructed on the substrate of isotropic material.

3. The two-dimensional optical path device based on hyperbolic anisotropic metamaterial according to claim 2, characterized in that: The substrate is a quartz substrate.

4. The two-dimensional optical path device based on hyperbolic anisotropic metamaterial according to claim 3, characterized in that: The transmission channel structure is a two-dimensional metamaterial structure. A metal film is plated on the quartz substrate by electron beam evaporation, and then focused ion beam etching is used to prepare strip structures with different period sizes to achieve a hyperbolic metasurface structure that is equivalent to a uniform medium as the transmission channel structure.

5. The two-dimensional optical path device based on hyperbolic anisotropic metamaterial according to claim 3, characterized in that: The input end structure is a two-dimensional metamaterial structure. A metal film is plated on the quartz substrate by electron beam evaporation, and then focused ion beam etching is used to prepare structures with different period sizes that can diffract incident light as the input end structure.

6. The two-dimensional optical path device based on hyperbolic anisotropic metamaterial according to claim 5, characterized in that: The input end structure adopts a grating structure or a structural defect structure. The input end structure is designed to provide a wave vector direction that points from the input end structure to the direction of the transmission channel structure, and is located within the optical axis plane of the input end structure and the transmission channel structures on both sides.

7. The two-dimensional optical path device based on hyperbolic anisotropic metamaterial according to claim 4, characterized in that: It also includes an output end structure arranged on the outside of the transmission channel structure on both sides, the output end structure is arranged on the quartz substrate, close to one end of the transmission channel structure, and is separated from the input end structure by the transmission channel structure. The output end structure uses a focused ion beam to etch a metal nano-cylinder array with the same horizontal and vertical period size on the metal film, so as to decouple the transmission information in the transmission channel structure into free space.

8. The two-dimensional optical path device based on hyperbolic anisotropic metamaterial according to claim 4, characterized in that: Each of the transmission channel structures includes two transmission interfaces, the interface between the metal film structure and the air is the upper air-side interface, and the interface between the metal film structure and the quartz substrate is the lower substrate-side interface.

9. The two-dimensional optical path device based on hyperbolic anisotropic metamaterial according to claim 8, characterized in that: The specific method of realizing multiplexing and routing control of information channel transmission based on the spin-momentum locking principle by the anisotropic interaction of the incident wave polarization and the transmission channel structure is as follows: When linear polarization is incident on the input end structure to emit diffracted light, the diffracted light simultaneously excites the upper air side interface of one of the two groups of transmission channel structures on both sides of the input end structure to transmit right-handed circularly polarized light, and the lower base side interface to transmit left-handed circularly polarized light, and the upper air side interface of the transmission channel structure on the other side to transmit left-handed circularly polarized light, and the lower base side interface to transmit right-handed circularly polarized light; When right-handed circularly polarized light is incident on the input end structure to emit diffracted light, the diffracted light excites two transmission interfaces of the transmission channel structure on one side of the input end structure, the upper air side interface carries the right-handed polarization state of photons, and the lower substrate side interface carries the left-handed polarization state of photons; When left-handed circularly polarized light is incident on the input end structure to emit diffracted light, it excites the two transmission interfaces of the transmission channel structure on the other side of the input end structure. The upper air side interface carries the left-handed polarization state of photons, and the lower substrate side interface carries the right-handed polarization state of photons.

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