Metastructure surface device capable of programmable regulation and control of energy collimation propagation and regulation and control method thereof

Abstract

The invention relates to a metasurface device capable of programmable regulation and control of energy collimation propagation and a regulation and control method thereof, and the metasurface device comprises a metasurface material which comprises a substrate layer and a plurality of functional units which are periodically arranged on the substrate layer in a two-dimensional manner and can respectively perform in-situ rotation relative to the substrate layer, each functional unit is configured to generate electromagnetic response when being excited, and the electromagnetic response can change along with the change of the rotation angle of the functional unit; the plurality of driving parts are mounted on the substrate layer and are respectively in driving connection with the plurality of functional units; and the control module comprises a control circuit and a programmable program, the control circuit is electrically connected to each driving part, and the programmable program is used for controlling the control circuit to control all or part of the driving parts so as to realize overall or regional or independent dynamic regulation and control of the rotation angle of the functional unit. The method has the characteristics of programmability, continuous adjustability, reconfigurability as required and the like, and can realize arbitrarily customized polariton collimation mode distribution.

Description

Technical Field

[0001] The present invention relates to the field of optical material design, and particularly to a metasurface device capable of programmably regulating the collinear propagation of energy and a regulation method thereof. Background Art

[0002] In two-dimensional van der Waals materials, a series of novel physical phenomena related to the twist angle can be realized by controlling the interlayer twist angle. This discovery not only promotes the rapid development of the field of twistronics, but also opens up a new way to regulate material properties using the degree of freedom of the twist angle, opening up a broader space for the research of materials science. For example, a twist optical structure with a Moiré configuration can support unique light-matter interactions. However, most of the existing research work often involves relatively complex preparation processes and difficult-to-adjust structural limitations, which to a certain extent hinder their practical applications.

[0003] Hyperbolic polaritons are a hybrid excitation state generated by the strong coupling of photons and quasiparticles, and can exhibit many unique properties. In recent years, they have been fully explored in various anisotropic materials with hyperbolic dispersion. Among them, hyperbolic metasurfaces are considered to be another platform for exploring richer twist-related phenomena due to their compactness and tunability. At the same time, the introduction of the twist angle can further utilize the anisotropy of hyperbolic metasurfaces to achieve diverse regulation of polaritons. However, the related research still mainly focuses on adjusting the structure of interlayer rotation, which ignores the inherent ability of metasurfaces to precisely control sub-wavelength units, which is difficult to achieve in two-dimensional materials.

[0004] Meanwhile, hyperbolic polaritons are often accompanied by the existence of a dispersion topological phase transition, that is, the material dispersion curve undergoes a process from a closed ellipse to an open hyperbola. Among them, in the critical region of the phase transition, polaritons will exist in a nearly diffraction-free collinear propagation mode, showing extremely localized, highly collinear and relatively low-loss characteristics, which also gives them unique advantages compared with other polariton modes. However, the regulation of collinear polaritons has not been deeply developed. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a metasurface device capable of programmably regulating the collinear propagation of energy and a regulation method thereof, which has the characteristics of being programmable, continuously adjustable, and reconfigurable on demand, and can realize an arbitrarily customized polariton collinear mode distribution.

[0006] The present invention is realized by the following scheme. A metasurface device capable of programmably regulating the collinear propagation of energy includes:

[0007] The metasurface material includes a substrate layer and a plurality of functional units; wherein, the plurality of functional units are arranged two-dimensionally periodically on the substrate layer and can be rotated in situ relative to the substrate layer respectively, and each functional unit is configured to generate an electromagnetic response when excited by an excitation source, and the electromagnetic response can vary with the change of the rotation angle of the functional unit;

[0008] A plurality of driving members are mounted on the substrate layer and are drivingly connected to the plurality of functional units one by one;

[0009] The control module includes a control circuit and a programmable program. The control circuit is electrically connected to each driving member, and the programmable program is used to control the control circuit to control all or part of the driving members to achieve overall, regional or individual dynamic regulation of the rotation angle of the functional units.

[0010] A further improvement of the metasurface device of the present invention is that: the functional unit includes a dielectric layer provided on the substrate layer and a metal layer fixed on the side of the dielectric layer facing away from the substrate layer; the driving member includes a motor, and the motor is mounted on the side of the substrate layer facing away from the dielectric layer, and the output shaft of the motor can rotatably pass through the substrate layer and is fixedly connected to the corresponding dielectric layer.

[0011] A further improvement of the metasurface device of the present invention is that the metal layer is a double-open ring structure.

[0012] The present invention also provides an energy collimated propagation regulation method, including the steps of:

[0013] Providing the metasurface device as described above and making the initial angles of all functional units in the metasurface material the same;

[0014] Providing an excitation source, placing the excitation source on one side of the metasurface device, and setting the excitation source to a specified operating frequency;

[0015] Based on the relationship between the change of the in-situ rotation angle of the functional unit and the deflection angle of the collimated polariton, the in-situ rotation angle is regulated with a single functional unit as the smallest scale, and predicted with the help of the dispersion curve, so that the regulated metasurface device has a polariton magnetic field distribution consistent with the target trajectory of energy collimated propagation under the excitation of the excitation source.

[0016] A further improvement of the regulation method of the present invention is that when regulating the in-situ rotation angle: dividing the target trajectory of energy collimated propagation into different trajectory segments according to the propagation direction, dividing the metasurface device with the excitation source as the starting point, and making each region correspond to one of the trajectory segments, wherein each region includes a plurality of the functional units;

[0017] Correspondingly adjust the rotation angles of the functional units in the adjacent front and rear regions according to the deflection angle relationship between the adjacent front and rear trajectory segments.

[0018] A further improvement of the regulation method of the present invention lies in that when correspondingly adjusting the rotation angles of the functional units in the adjacent front and rear regions according to the deflection angle relationship between the adjacent front and rear trajectory segments, if the latter trajectory segment is the last trajectory segment of the energy collimated propagation target trajectory, then select some functional units from the multiple functional units at the end of the region corresponding to the latter trajectory segment in a way of extracting every other one and perform another angle rotation, and the said another angle differs from the rotation angles of other functional units in the corresponding region by 70°-110°.

[0019] A further improvement of the regulation method of the present invention lies in that when dividing the metasurface device into regions, first divide the regions sequentially along the incident direction of the excitation source, and make each of the said regions have the same width in the direction perpendicular to the incident direction, and then further divide the regions corresponding to at least two trajectory segments simultaneously until each region corresponds to only one trajectory segment; wherein, when further dividing the regions corresponding to at least two trajectory segments simultaneously, determine the number of functional units in the further divided regions according to the energy strength of the corresponding trajectory segments, and the determination principle is that the stronger the energy of the trajectory segment, the more the number of functional units in the corresponding region.

[0020] A further improvement of the regulation method of the present invention lies in that the certain operating frequency satisfies that the metasurface device is always in the polariton collimation mode when the functional units are at different rotation angles.

[0021] Through the setting of the driving member and the control module, the metasurface material of the present invention can independently regulate the in-situ twist angle distribution at the unit scale, can combine regions with different in-situ twist angles, and realize the regulation functions for the collimated polariton propagation path such as full-angle guiding, asymmetric power distribution, continuous trajectory bending, etc., and further can realize an arbitrarily customized polariton collimation mode distribution. In addition, the metasurface material of the present invention has the characteristic of being reconfigurable and can utilize the program to control the change of the in-situ twist angle of the functional units, so there is no need for cumbersome adjustment steps when performing function switching. Description of the Drawings

[0022] Figure 1 Shows a schematic diagram of the working state of the metasurface device of the present invention.

[0023] Figure 2 Shows a schematic diagram of the structure of the functional unit in the metasurface device of the present invention.

[0024] Figure 3Shows the dispersion topological property diagram of the polariton modes supported by the metasurface device of the present invention.

[0025] Figure 4 Shows the comparison schematic diagram of the theoretical calculated three-dimensional dispersion surface corresponding to the metasurface device with different in-situ rotation angles and the polariton magnetic field distribution of simulation and experimental measurement.

[0026] Figure 5 Shows the Figure 4 k-space distribution diagram obtained by Fourier transform of the simulation and experimental results.

[0027] Figure 6 Shows the schematic diagram of the metasurface device with different in-situ rotation angle distributions realizing the deflection of collimated polaritons at different angles.

[0028] Figure 7 Shows the direction diagram of the polaritons propagating in the deflected area under different combinations of in-situ rotation angles.

[0029] Figure 8 Shows the schematic diagram of the metasurface device of the present invention realizing the function of splitting collimated polaritons into different ratios.

[0030] Figure 9 Shows the schematic diagram of the metasurface device of the present invention realizing the continuous bending function regulation of collimated polaritons.

[0031] Figure 10 Shows the schematic diagram of the in-situ rotation angle distribution of the metasurface device of the present invention regulating the propagation trajectory of collimated polaritons to simulate the letter 'T' and the corresponding polariton magnetic field distribution diagram.

[0032] Figure 11 Shows the schematic diagram of the in-situ rotation angle distribution of the metasurface device of the present invention regulating the propagation trajectory of collimated polaritons to simulate the letter 'J' and the corresponding polariton magnetic field distribution diagram. Detailed implementation manners

[0033] In order to solve the problem that the existing polariton regulation devices cannot accurately regulate the collimated mode distribution of polaritons, the present invention provides a metasurface device for programmable regulation of energy collimated propagation and its regulation method, which has the characteristics of programmability, continuous adjustability, on-demand reconfigurability, etc., and can realize any customized collimated mode distribution of polaritons. The following further illustrates the metasurface device for programmable regulation of energy collimated propagation and its regulation method with specific embodiments in conjunction with the drawings.

[0034] Refer to Figure 1 and Figure 2As shown in the figure, a metasurface device for programmable regulation of energy collimated propagation includes a metasurface material 1, a plurality of driving members 2, and a control module 3. Among them: The metasurface material 1 includes a base layer 11 and a plurality of functional units 12. The plurality of functional units 12 are arranged two-dimensionally and periodically on the base layer 11 and can be rotated in situ relative to the base layer 11 respectively. Each functional unit 12 is configured to generate an electromagnetic response when excited by an excitation source 5, and the electromagnetic response can vary with the change of the rotation angle of the functional unit 12. The plurality of driving members 2 are mounted on the base layer 11 and are drivingly connected to the plurality of functional units 12 one by one. The control module 3 includes a control circuit and a programmable program. The control circuit is electrically connected to each driving member 2, and the programmable program is used to control the control circuit to control all or part of the driving members 2 to achieve overall, regional, or individual dynamic regulation of the rotation angle of the functional unit 12.

[0035] In some embodiments, as Figure 2 shown in the figure, the functional unit 12 includes a dielectric layer 121 disposed on the base layer 11 and a metal layer 122 fixed on the side of the dielectric layer 121 facing away from the base layer 11. The metal layer 122 is a double-open ring structure, which can be a circular metal ring (such as a copper ring), and a small section is symmetrically cut off at two opposite positions. The purpose is to form an equivalent capacitance, and the use of metal is to form an inductance. By forming the capacitance and inductance, the functional unit 12 can generate an electromagnetic response when excited by the excitation source 5, and then form a polariton. The metal layer is not limited to the copper ring with this structural form. The dielectric layer 121 is circular and has a diameter slightly larger than that of the metal layer 122. The dielectric layer 121 is used to support and fix the metal layer 122. The area of the base layer 11 corresponding to each functional unit 12 is square, and the side length is greater than the diameter of the dielectric layer 121. The driving member 2 includes a motor, preferably a stepping motor. The motor is mounted on the side of the base layer 11 facing away from the dielectric layer 121, and the output shaft of the motor can rotatably pass through the base layer 11 and is fixedly connected to the corresponding dielectric layer 121. The output shaft of the motor drives the dielectric layer 121 to rotate in situ, and then drives the metal layer 122 to rotate in situ. The rotation angle and rotation direction of the output shaft of the motor are controlled and adjusted by the control circuit connected thereto. The control circuit is controlled by a programmable program, and the programmable program can be programmed by a computer 4 according to user needs to achieve overall, regional, or individual regulation of the rotation angle of the functional unit 12 in situ, and can be dynamically switched.

[0036] By setting multiple such driving members 2 and the control module 3, the metasurface material 1 can independently regulate the in-situ twist angle distribution at the unit scale, and can combine regions with different in-situ twist angles to achieve control functions for the propagation path of collimated polaritons such as full-angle guiding, asymmetric power distribution, and continuous trajectory bending. Furthermore, an arbitrarily customized polariton collimation mode distribution can be achieved.

[0037] An energy collimated propagation control method based on the metasurface device as described above, comprising the steps of:

[0038] Step 1: Provide the metasurface device as described above, and make the initial angles of all functional units in the metasurface material the same.

[0039] Step 2: Provide an excitation source, place the excitation source on one side of the metasurface device, and set the excitation source to a specified operating frequency.

[0040] Step 3: Based on the relationship between the change in the in-situ rotation angle of the functional unit and the deflection angle of the collimated polariton, regulate the in-situ rotation angle at the smallest scale of a single functional unit, and predict with the help of the dispersion curve, so that the regulated metasurface device has a polariton magnetic field distribution consistent with the target trajectory of the energy collimated propagation under the excitation of the excitation source.

[0041] The principle of the above control method will be described in detail below through simulation and specific experiments using a specific metasurface device:

[0042] Referring to Figure 1 and Figure 2 as shown, Figure 1 shows a schematic diagram of the working state of a metasurface device, Figure 2The structural schematic diagram of the functional unit in the metasurface device is shown. The metasurface device includes a metal layer 122, a dielectric layer 121, a substrate layer 11, and a stepper motor (i.e., the driving member 3) arranged in sequence. Among them, the metal layer 122 and the dielectric layer 121 constitute the basic functional unit 12. The metal layer 122 is made of a copper ring with a thickness of 0.035 mm, an outer diameter of 10 mm, and a width of 1 mm. An opening slit is provided on each of the opposite sides of the copper ring, and the slit width is 1 mm. The dielectric layer 121 is made of F4B board with a thickness of 1.6 mm, a dielectric constant of 2.2, and a loss tangent value of 0.0079. The dielectric layer 121 is made into a circle with a diameter of 10.2 mm. The number of the functional units 12 is multiple, and they are arranged on the substrate layer 11 in a two-dimensional periodic arrangement manner, and the period length of the arrangement is 11 mm. The metasurface device further includes a control module 3 that uses a programmable control circuit to partially or wholly adjust the in-situ rotation angle of the functional unit 12. Under the near-field excitation of the excitation source 5, the metasurface material 1 supports the generation of polaritons, and its propagation behavior is regulated by the dispersion characteristics determined by the in-situ rotation angle of each functional unit 12. As the Figure 1 figure shows, the metasurface material 1 with the functional unit 12 that rotates integrally at a fixed angle can deflect the collimated polaritons by a certain angle.

[0043] In addition, since the polariton mode supported by the metasurface device is related to the working frequency and the in-situ rotation angle, by using the full-wave simulation technology (CST) microwave studio software based on the finite integration method to calculate and analyze the functional unit, the polariton dispersion characteristics corresponding to the metasurface material formed by the two-dimensional periodic arrangement of the units with a specific in-situ rotation angle can be obtained. As Figure 3 shown, Figure 3 figure shows the dispersion topological properties of the polariton modes corresponding to different in-situ rotation angles in the working frequency range of 6.4 GHz to 7.6 GHz. It can be seen from the figure that on the one hand, with the change of the working frequency, the dispersion topology of the polariton mode will change; on the other hand, it is noted that there is always a polariton collimation mode between the working frequencies of 6.8 GHz and 7 GHz, and its existence does not disappear with the change of the in-situ rotation angle. Therefore, the subsequent regulation verification all adopts this working frequency to facilitate better observation of the distribution law of polaritons.

[0044] Regarding the relationship between the change of the in-situ rotation angle of the functional unit and the deflection angle of the collimated polaritons.

[0045] Four groups of metasurface materials are selected, which are two-dimensionally arranged by functional units with in-situ rotation angles of 0°, 30°, 60°, and 90° respectively. The three-dimensional dispersion surfaces of them in the Brillouin zone are plotted respectively. Then, the magnetic field distribution is simulated and experimentally measured at a fixed operating frequency (selected from 6.8 GHz to 7 GHz). The results are as Figure 4 shown, Figure 4 which shows a comparison diagram of the theoretically calculated three-dimensional dispersion surface and the polariton magnetic field distribution measured by simulation and experiment corresponding to these four metasurface materials. It can be seen from the figure that the supported collimated polaritons basically always propagate at a specific angle in a non-diffracting manner. As the in-situ rotation angle changes, this deflection angle also gradually increases. To determine the consistency of the theoretical, simulation, and experimental results, the Fourier transform is performed on the polariton magnetic field distributions obtained from simulation and experiment, which can convert the field distribution in real space into the wave vector distribution in k-space and compare it with the theoretical calculation. The results are as Figure 5 shown, Figure 5 which shows the k-space distribution diagrams obtained by Fourier transforming the simulation and experimental results of Figure 4 . The dotted lines in the figure are the theoretical calculation results. It can be seen from the figure that within a reasonable error range, the results of the Fourier transform and the theoretical calculation are in good agreement, which indicates that the propagation of polaritons can be well predicted by the calculated dispersion. In summary, adjusting the in-situ rotation angle of the functional unit can control the propagation of collimated polaritons and can be predicted with the help of the dispersion curve.

[0046] When performing the regulation of the in-situ rotation angle: the target trajectory of energy collimated propagation is divided into different trajectory segments according to the propagation direction. The metasurface device is divided into regions starting from the excitation source, and each region corresponds to one of the trajectory segments. Specifically, the regions are sequentially divided along the incident direction of the excitation source first, and each region has the same width in the direction perpendicular to this incident direction. Then, the regions corresponding to at least two trajectory segments are further divided until each region corresponds to only one trajectory segment, and each region includes multiple functional units. It should be noted that when further dividing the regions corresponding to at least two trajectory segments, the number of functional units in the further divided region is determined according to the energy strength of the corresponding trajectory segments. The determination principle is: the stronger the energy of the trajectory segment, the more the number of functional units in the corresponding region. The rotation angles of the functional units in the adjacent front and rear regions are adjusted according to the deflection angle relationship between the adjacent front and rear trajectory segments. The combinations of different regions and different angles can play different regulatory roles in the propagation of collimated polaritons, and then any target trajectory of energy collimated propagation that is desired can be obtained. Next, several specific regulation methods are used for analysis and verification.

[0047] 1. By combining two regions with different in-situ rotation angles, the originally collimated propagating polaritons can be deflected by a specific angle, such as Figure 6 shown, Figure 6 Fig. Figure 6 shows a schematic diagram of a metasurface device with different in-situ rotation angle distributions for deflecting collimated polaritons at different angles. Among them: the left figure is a schematic diagram of the in-situ rotation angle distribution, and the pentagram represents the position of the excitation source; the middle figure is a simulated magnetic field distribution diagram of collimated polaritons; the right figure is a partial experimental magnetic field distribution diagram of collimated polaritons, corresponding to the area within the dashed box. It can be seen from the figure that for the case where the in-situ rotation angle is all 0°, the polaritons propagate along the horizontal direction and basically do not show diffraction at a propagation distance of several wavelengths. For the combined case of in-situ rotation angles of 0° and 60°, after passing through the interface between the two regions, the polaritons are deflected and continue to propagate at an inclined angle. When the in-situ rotation angle of the right region is further increased to 90°, the polaritons are almost completely deflected to the vertical direction. It is worth mentioning that due to the 90° rotation angle restoring the symmetry of the functional unit with respect to the horizontal direction, the polaritons can propagate in both the upward and downward directions simultaneously after deflection.

[0048] 2. Further analyze the directivity of the propagated polaritons after deflection, such as Figure 7 shown, Figure 7 Fig. Figure 7 shows the direction diagram of the propagated polaritons in the deflected region under different combinations of in-situ rotation angles, where the angle of the left region is fixed at 0°. It can be seen from the figure that for the cases where the in-situ rotation angle of the right region in the combination takes different values, the deflected polaritons can maintain good directivity. And theoretically, a suitable combination of in-situ rotation angles can achieve arbitrary angle guiding of polaritons.

[0049] 3. Consider further dividing the in-situ rotation angle distribution of the right region. Such as Figure 8 shown, Figure 8 Fig. Figure 8 shows a schematic diagram of a metasurface device for realizing the beam splitting function of collimated polaritons in different proportions. Among them: the left figure is a schematic diagram of the in-situ rotation angle distribution, and the pentagram represents the position of the excitation source; the middle figure is a simulated magnetic field distribution diagram of collimated polaritons; the right figure is a partial experimental magnetic field distribution diagram of collimated polaritons, corresponding to the area within the dashed box. It can be seen from the figure that the right region is set with opposite rotation angles, namely 45° and -45°. The originally collimated propagating polaritons are distributed into two propagation channels with opposite directions at the interface, and the deflected polaritons still maintain the characteristics of directional and non-diffractive propagation. In addition, due to the different numbers of functional units corresponding to the two in-situ rotation angles, the proportion of polaritons in the two channels is slightly different, and the energy strengths of the presented trajectory segments are also different.

[0050] 4. Consider dividing the in-situ rotation angle distribution of the right region in another form, that is, setting an increasing in-situ rotation angle for three parts in equal angular differences. As Figure 9 shown, Figure 9 Fig. shows a schematic diagram of the metasurface device realizing the continuous bending function regulation of collimated polaritons. Among them: the left figure is a schematic diagram of the in-situ rotation angle distribution, and the pentagram indicates the position of the excitation source; the middle figure is a simulated magnetic field distribution diagram of collimated polaritons; the right figure is a partial experimental magnetic field distribution diagram of collimated polaritons, corresponding to the area within the dashed box. It can be seen from the figure that the originally horizontally propagating polaritons become more inclined after passing through each interface, and the deflection angle in each region is determined by the corresponding dispersion. If the rotation angle is set more precisely, the bending behavior of the polaritons can be made smoother.

[0051] 5. In order to fully utilize the ability of the metasurface to independently adjust each functional unit, the in-situ rotation angle of the functional unit is set in a more precise way to realize arbitrary regulation of the propagation trajectory of collimated polaritons. For the sake of simplicity, the vertical direction is set as the reference 0°.

[0052] As Figure 10 shown, Figure 10 Fig. shows a schematic diagram of the in-situ rotation angle distribution of the metasurface device regulating the propagation trajectory of collimated polaritons to simulate the letter 'T' and the corresponding magnetic field distribution diagram of polaritons. Among them, the pentagram indicates the position of the excitation source. First, set the in-situ rotation angle of the functional units in a certain area above the excitation source to 0°, which can support the collimated mode of polaritons; then set the in-situ rotation angle of the functional units in the uppermost area to 90°, and additionally set a functional unit to 0°, which can make the polaritons more efficiently transmitted to the deflection area and deflected to propagate to the left and right sides; finally, set a section of functional units in the area below the excitation source to be arranged alternately with in-situ rotation angles of 0° and 90°. Because of the large angular difference (90°) between the two in-situ rotation angles, the mismatch caused by the high contrast of the dispersion can effectively suppress the downward propagation of polaritons. An angular difference selected from 70° to 110° can have this effect. After the above operations, the propagation trajectory of collimated polaritons in the magnetic field distribution diagram is regulated into the shape of the letter 'T'.

[0053] In addition, as Figure 11 shown, Figure 11The schematic diagram of the in-situ rotation angle distribution of the metasurface device to simulate the letter 'J' in regulating the propagation trajectory of the collimated polaritons and the corresponding polaritons magnetic field distribution diagram are shown, where the five-pointed star represents the position of the excitation source. First, the functional units in the area near the excitation source are set to an in-situ rotation angle of 0°, which can support the polaritons collimation mode; then the lower area is divided into two parallel partitions, and the functional units in the two partitions are set to increase the in-situ rotation angle by 10° and decrease the in-situ rotation angle by -10°, respectively, so that the polaritons can be bent 180 degrees continuously and smoothly; finally, the functional units in the lowermost area and the bending end are set to alternately arrange the in-situ rotation angle of 0° and the in-situ rotation angle of 90°, the former suppresses unnecessary scattering during the bending process, and the latter cuts off the upward propagation of the polaritons; after the above operations, the propagation trajectory of the collimated polaritons in the magnetic field distribution diagram is regulated to the shape of the letter 'J'.

[0054] From the above-mentioned 'T'-shaped and 'J'-shaped controls, it can be found that: when the original propagation trajectory needs to be truncated (usually the last trajectory segment of the corresponding energy collimated propagation target trajectory), some functional units 12 can be screened out from the multiple functional units 12 at the end of the corresponding area in an alternate manner and subjected to high-contrast angular rotation, that is, the angle difference between the two in-situ rotation angles is 70° to 110°. The mismatch caused by the high contrast of the dispersion can effectively suppress the downward propagation of polaritons.

[0055] Through the verification of the above-mentioned control method, it can be known that the metasurface device of the present invention can realize in-plane directional propagation, beam splitting, bending and other functions by setting different in-situ rotation angles for functional units in different regions, thereby supporting polaritons of different propagation types. The metasurface device of the present invention can also use other polariton modes to realize more unique control functions, and can also be expanded to the control of polaritons in other frequency bands by changing the geometric dimensions. The present invention can generate a collimated polariton propagation trajectory with a specific pattern by independently controlling the in-situ rotation angle of each unit in a complex manner, and the specific control method is mainly determined by the dispersion characteristics related to the rotation angle. This not only combines the emerging corner electronics and optical metasurface control, and provides a new way to dynamically control polaritons at the subwavelength scale, but also is expected to be applied in the fields of adaptive photonic circuits, quantum information technology and subwavelength imaging. Further, it can also be extended to mechanical systems, acoustic systems, thermal systems, etc.

[0056] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. A metasurface device capable of programmable control of energy collimation propagation, characterized in that: include: A metasurface material, comprising a base layer and a plurality of functional units; wherein the plurality of functional units are two-dimensionally periodically arranged on the base layer and can be respectively rotated in situ relative to the base layer, each of the functional units is configured to generate an electromagnetic response when excited by an excitation source, and the electromagnetic response can change with the change of the rotation angle of the functional unit; A plurality of driving members are installed on the base layer and are drivingly connected to the plurality of functional units in a one-to-one correspondence; The control module includes a control circuit and a programmable program, wherein the control circuit is electrically connected to each of the driving components, and the programmable program is used to control the control circuit to control all or part of the driving components to achieve overall, regional or individual dynamic regulation of the rotation angle of the functional unit.

2. The metasurface device for programmable control of energy collimation propagation as claimed in claim 1, characterized in that: The functional unit includes a dielectric layer arranged on the base layer and a metal layer fixed on the side of the dielectric layer facing away from the base layer; the driving component includes a motor, which is installed on the side of the base layer facing away from the dielectric layer, and the output shaft of the motor can rotatably pass through the base layer and is fixedly connected to the corresponding dielectric layer.

3. The metasurface device for programmable control of energy collimation propagation according to claim 1, characterized in that: The metal layer is a double-opening ring structure.

4. A method for controlling energy collimation and propagation, characterized in that: Includes steps: Providing a metasurface device as claimed in claim 1, and making the initial angles of all functional units in the metasurface material the same; Providing an excitation source, placing the excitation source on one side of the metasurface device, and setting the excitation source to a specified operating frequency; Based on the relationship between the change of the in-situ rotation angle of the functional unit and the deflection angle of the collimated polaritons, the in-situ rotation angle is regulated with a single functional unit as the minimum scale, and with the help of dispersion curves, it is predicted that the regulated metasurface device will have a polariton magnetic field distribution consistent with the target trajectory of energy collimation propagation under the excitation of the excitation source.

5. The energy collimation propagation control method according to claim 4, characterized in that: When the in-situ rotation angle is regulated: the energy collimation propagation target trajectory is divided into different trajectory segments according to the propagation direction, the metasurface device is divided into regions with the excitation source as the starting point, and each region corresponds to one of the trajectory segments, wherein each region includes a plurality of the functional units; The rotation angles of the functional units in the front and rear adjacent areas are correspondingly adjusted according to the deflection angle relationship between the front and rear adjacent track segments.

6. The energy collimation propagation control method according to claim 5, characterized in that: When adjusting the rotation angles of the functional units in the front and rear adjacent areas according to the deflection angle relationship between the front and rear adjacent trajectory segments, if the latter trajectory segment is the last trajectory segment of the energy collimated propagation target trajectory, some functional units are selected from the multiple functional units at the end of the area corresponding to the latter trajectory segment in an alternate extraction manner and rotated at another angle, and the other angle differs from the rotation angles of other functional units in the corresponding area by 70° to 110°.

7. The energy collimation propagation control method according to claim 5, characterized in that: When dividing the metasurface device into regions, the regions are first divided sequentially along the incident direction of the excitation source, and each of the regions has the same width perpendicular to the incident direction, and then the regions corresponding to at least two trajectory segments are further divided until each region corresponds to only one trajectory segment; wherein, when further dividing the regions corresponding to at least two trajectory segments, the number of functional units in the further divided regions is determined according to the energy strength of the corresponding trajectory segments, and the determination principle is that the stronger the energy of the trajectory segment, the greater the number of functional units corresponding to the region.

8. The energy collimation propagation control method according to claim 4, characterized in that: The certain operating frequency satisfies that the metasurface device is always in the polariton alignment mode when the functional units are at different rotation angles.

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