A reconfigurable metasurface dynamically regulating topological features of electromagnetic polaritons

Abstract

This invention relates to a reconfigurable metasurface for dynamically controlling the topological characteristics of electromagnetic polaritons. The invention comprises a basic functional unit combined with a varactor diode periodically extended in a two-dimensional plane. The basic functional unit includes a single-layer dielectric, two layers of metal, and metallized vias. By changing the applied bias voltage, reconfigurable topological transmission of the polariton dispersion topology can be achieved, from open ellipses to straight lines, hyperbolas, and circles. Utilizing the wavefront characteristics under different dispersion topologies, broadband field channelization, dynamic focusing, and reconfigurable polariton circuit design can be realized. This invention further improves the flexibility of surface wave propagation and guidance manipulation, possessing advantages such as low dimensionality, continuous controllability, and high-speed response. It is beneficial for the integration of electromagnetic components in modern near-field information processing systems, the design of photonic integrated circuits and multifunctional programmable plasmon polariton devices, and has broad application prospects in near-field sensing, positioning, high-resolution imaging, and energy reuse.

Description

Technical Field

[0001] This invention belongs to the field of artificial electromagnetic metamaterials, specifically relating to a reconfigurable metasurface that dynamically controls the topological characteristics of electromagnetic polaritons. Background Technology

[0002] Electromagnetic metamaterials draw inspiration from the composition of natural materials, being created by carefully designed artificial atoms with unique electromagnetic responses arranged in a specific pattern (usually periodic). As planar electromagnetic metamaterials, electromagnetic metasurfaces not only allow for flexible control of the basic characteristics of electromagnetic waves (amplitude, phase, polarization, dispersion, etc.), but also possess advantages such as low loss, thinness, small size, light weight, and ease of fabrication. They are currently widely used in the design of advanced electromagnetic devices.

[0003] Polaritons are photonic composite quasiparticles generated by strong coupling between light and electron oscillations. Due to their exotic characteristics in manipulating the interaction between light and matter, they have been extensively studied in various material systems (low-dimensional quantum nanomaterials, photonic crystals, metamaterials, etc.). In recent years, hyperbolic polaritons in extremely anisotropic material systems have attracted widespread attention because their unique hyperbolic dispersion characteristics (optical dispersion isofrequency lines exhibit hyperbolic patterns) can guide a series of interesting physical phenomena, such as strong electromagnetic field localization, enhanced spontaneous emission, and high-momentum photon modes.

[0004] The rapid development of modern science and technology has placed higher demands on electromagnetic devices. Devices with single functions and poor compatibility are no longer sufficient to meet the increasingly complex electromagnetic environments. The design of emerging electromagnetic devices is also showing a trend towards multifunctionality, reconfigurability, and intelligence. Correspondingly, the dynamic control of polariton dispersion characteristics and reconfigurable topological transmission (the change of dispersive isofrequency lines from ellipses to hyperbolas) has become one of the current research hotspots in the field of electromagnetics. Based on this, it is hoped that advanced multifunctional plasmon devices can be designed and realized. At present, the main approach to achieving topological reconfigurability is through geometric transformation of the structure and adjustment of the intrinsic properties of low-dimensional van der Waals materials (such as refractive index and conductivity). However, the implementation scheme based on geometric transformation has inherent limitations in terms of control speed and accuracy, which seriously restricts its further development and application in high-speed response and high-robustness photonic integrated circuits and optoelectronic components; while the operating wavelength of natural hyperbolic materials such as graphene, molybdenum trioxide, and hexagonal boron nitride is limited by their crystal structure, thus limiting the control range and operating frequency band.

[0005] In summary, in order to further improve the flexibility and effectiveness of reconfigurable topology transmission and the design of corresponding multifunctional plasmonic devices, it is urgent to explore a solution that can achieve dynamic control of hyperbolic polariton dispersion characteristics, while possessing low-dimensionality, continuous controllability, high-speed response, and real-time on-demand reconfigurability. Summary of the Invention

[0006] Purpose of the Invention: The main objective of this invention is to overcome the aforementioned difficulties and provide a reconfigurable metasurface for dynamically controlling the topological characteristics of electromagnetic polaritons. By combining the functional units of the electromagnetic metasurface with a varactor tube, the applied DC bias voltage can be adjusted to achieve dynamic control of the polariton dispersion characteristics. This allows the designed electrically reconfigurable metasurface to support the switching of isofrequency lines between ellipses, straight lines, hyperbolas, and circles within the same frequency band, and enables the design of surface wave manipulation, propagation, and guidance functions.

[0007] Technical solution: To achieve the above objectives, the technical solution adopted by this invention is as follows:

[0008] A reconfigurable metasurface for dynamically controlling the topological characteristics of electromagnetic polaritons is constructed by periodically extending basic functional units loaded with varactor diodes in a two-dimensional plane. The basic functional unit structure includes, from top to bottom, a first metal patch layer, a dielectric layer, and a second metal patch layer. The first and second metal patch layers are connected by a metallized via located at the center of the structural unit. The first metal patch layer is anisotropic. A ring-shaped metal structure centered on the metallized via is removed from the middle of the first or second metal patch layer. The varactor diode is connected across the metal patch regions inside and outside the ring formed after the removed ring-shaped metal structure.

[0009] Preferably, the first metal patch layer is a centrally symmetrical complementary I-shaped geometric pattern; each half of the first metal patch layer of two adjacent units together forms an I-shaped groove; the two ends of the I-shaped groove are straight lines, arcs or arrows.

[0010] Preferably, the annular metal structure is removed from the middle of the second metal patch layer. The annulus is a square ring or a circular ring, and the inner ring side length / diameter of the square ring / circular ring is greater than the diameter of the metallized via.

[0011] Preferably, the varactor diode is connected to a first metal patch layer and a second metal patch layer, and the first and second metal patch layers are respectively connected to the positive and negative terminals of a DC voltage source.

[0012] In the embodiments, the metasurface supports the generation and propagation of hyperbolic polaritons within a specific frequency band, and supports polaritons with circular, elliptical, and linear topologies in other frequency bands. By applying different bias voltages and simultaneously changing the capacitance values ​​of the varactors loaded in all basic functional units, reconfigurable topology transmission of polaritons can be achieved within a fixed frequency band. That is, the dispersion topology of polaritons can be dynamically, in real time, and continuously switched between open ellipses, straight lines, hyperbolas, and circles.

[0013] Furthermore, when the polariton dispersion topology switches between ellipse, straight line, and hyperbola, the wavefront of the polaritons exhibits the characteristics of outward divergence, no diffraction, and inward convergence, thereby enabling broadband field channelization and dynamic focusing.

[0014] Furthermore, it supports the design of planar reconfigurable multifunctional polariton circuits. The polariton circuit consists of multiple different regions, and the basic functional units in each region have the same capacitance value, while the basic functional units in adjacent regions have different capacitance values. By spatially trimming the dispersion topology combination of polaritons in different regions and applying corresponding bias voltages to different regions of the metasurface, polariton beam splitting, refraction control of polaritons, transmission suppression, and other functions can be realized. Moreover, high-speed and dynamic switching between functions can be achieved through electronic control.

[0015] In the embodiment, different voltages are applied to two adjacent regions 1 and 2 of the reconfigurable metasurface, so that the basic functional units in regions 1 and 2 exhibit quasi-linear and open elliptical topological features respectively under the corresponding applied capacitance values ​​(region 1 corresponds to a larger applied voltage). When polaritons propagate from region 1 to region 2, the function of polariton splitting can be realized at the interface between the two regions.

[0016] In the embodiment, different voltages are applied to two adjacent regions 1 and 2 of the reconfigurable metasurface, so that the basic functional units in regions 1 and 2 exhibit open elliptical and hyperbolic topological features respectively under the corresponding applied capacitance values ​​(region 1 corresponds to a larger applied voltage). When polaritons propagate from region 1 to region 2, the polaritons propagating along the two mirror symmetric directions in region 1 will undergo negative refraction at the interface between the two regions. If the applied voltage in region 1 is changed so that the corresponding basic functional units exhibit quasi-linear and open elliptical features respectively, the polaritons will undergo collimated refraction and positive refraction respectively.

[0017] In the embodiment, different voltages are applied to two adjacent regions 1 and 2 of the reconfigurable metasurface, so that the basic functional units in regions 1 and 2 exhibit quasi-linear and circular topological features respectively under the corresponding applied capacitance values ​​(region 1 corresponds to a larger applied voltage). When polaritons propagate from region 1 to region 2, the transmission of polaritons can be suppressed at the interface between the two regions. At this time, polaritons can hardly propagate in region 2.

[0018] Beneficial Effects: The reconfigurable metasurface for dynamically controlling the topological characteristics of electromagnetic polaritons proposed in this invention uses a varactor diode as the electronic control device. By changing the applied bias voltage, the dispersion characteristics of the basic functional units can be dynamically controlled, thereby dynamically controlling the dispersion topology of the polaritons. Compared with the prior art, this invention has the following advantages:

[0019] 1. The reconfigurable metasurface for dynamically controlling electromagnetic polariton topology features proposed in this invention supports reconfigurable topology transmission of polariton dispersion topology from open ellipses to straight lines, hyperbolas, and circles within a fixed frequency band. Benefiting from the rapid response characteristics of varactor devices during electronic control, the switching time of the dispersion topology is on the order of microseconds. Compared to mechanical control methods such as spatial rotation and folding deformation, the response time is significantly reduced, and the control accuracy is also significantly improved.

[0020] 2. By utilizing the wavefront characteristics under different dispersion topologies, this invention can further design and realize broadband field channelization and in-plane dynamic focusing functions. At the same time, it can also further design and realize electrically reconfigurable polariton circuits, which significantly improves the flexibility of polariton manipulation and is expected to further realize the design of programmable plasmonic circuits and planar multifunctional plasmonic devices.

[0021] 3. The electromagnetic metasurface proposed in this invention has advantages such as low dimensionality, ease of implementation, large controllability, continuous controllability, and real-time on-demand reconfigurability. It may be further developed in photonic integrated circuits and optoelectronic components, and has broad prospects in engineering applications such as high-resolution imaging, position sensing, energy reuse, and near-field information processing.

[0022] 4. The design scheme proposed in this invention has good scalability. In addition to the microwave band application shown in the embodiments, it can be extended to higher frequency bands such as millimeter waves and terahertz. The active control device can be a millimeter wave semiconductor device, liquid crystal, etc. Attached Figure Description

[0023] Figure 1 This is a schematic diagram illustrating the function of the metasurface in this invention to achieve polariton topology switching when the applied voltage changes.

[0024] Figure 2 This is a three-dimensional structural diagram of the basic unit of an embodiment of the present invention, wherein a varactor diode is loaded on the second metal patch layer of the basic functional unit, which is represented as an adjustable capacitive load.

[0025] Figure 3 The basic functional unit of this invention is a graph showing the relationship between the dispersion curve and the applied capacitance value when the polaritons propagate along the (a)x direction and (b)y direction, respectively. Each sub-graph shows the dispersion curve along different propagation directions when the applied capacitance values ​​are 0pF, 0.24pF, 0.30pF and 0.52pF.

[0026] Figure 4The momentum space isofrequency plots of the basic functional unit of this invention at an observation frequency of 6.1 GHz under the applied capacitance value are (a) 0 pF (open ellipse), (b) 0.24 pF (straight line), (c) 0.30 pF (hyperbola) and (d) 0.52 pF (circle).

[0027] Figure 5 These are front and back views of the processed sample according to an embodiment of the present invention (a).

[0028] Figure 6 These are simulation results of the near-field electric field distribution of a reconfigurable metasurface with dynamically controlled electromagnetic polariton topological features in this embodiment of the invention, corresponding to (a) an open elliptical topology, (b) a linear topology, (c) a hyperbolic topology and (d) a circular topology, respectively.

[0029] Figure 7 These are test results of the near-field electric field distribution of reconfigurable metasurface samples with dynamically controlled electromagnetic polariton topological features in embodiments of the present invention, corresponding to (a) open elliptical topology, (b) linear topology, (c) hyperbolic topology and (d) circular topology, respectively.

[0030] Figure 8 This is a graph showing the relationship between the topology transmission region and the loaded capacitance value and frequency in an embodiment of the present invention.

[0031] Figure 9 These are measured results of the broadband field channelization function implemented at frequencies of (a) 5.50 GHz, (b) 5.90 GHz, (c) 6.20 GHz and (d) 6.30 GHz, as designed in the embodiments of the present invention.

[0032] Figure 10 These are measured results of the in-plane dynamic focusing function designed in this embodiment of the invention at frequencies of (a) 6.10 GHz, (b) 6.30 GHz, (c) 6.43 GHz and (d) 6.60 GHz.

[0033] Figure 11 This is a schematic diagram of a planar electrically reconfigurable multifunctional polariton circuit in an embodiment of the present invention. Here, a planar electrically reconfigurable multifunctional polariton circuit composed of two different regions is used as an illustration.

[0034] Figure 12 This is a schematic diagram of the polariton beam splitting function implemented based on a planar electrically reconfigurable multifunctional polariton circuit in an embodiment of the present invention.

[0035] Figure 13 This is a schematic diagram illustrating the negative refraction function of polaritons based on a planar electrically reconfigurable multifunctional polariton circuit in an embodiment of the present invention.

[0036] Figure 14This is a schematic diagram of the polariton transmission suppression function implemented based on a planar electrically reconfigurable multifunctional polariton circuit in an embodiment of the present invention. Detailed Implementation

[0037] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, it should be understood that the present invention can be implemented in various forms. Some exemplary and non-limiting embodiments shown in the drawings and described below are not intended to limit the present invention to the specific embodiments described.

[0038] Reference Figure 1 This invention discloses a reconfigurable metasurface that dynamically modulates the topological characteristics of electromagnetic polaritons to support reconfigurable topological transport of polaritons. Specifically, as shown in the embodiments of this invention... Figure 1 As shown, the metasurface is fed by dipoles located in the bottom edge region, which can excite polaritons to be generated. At different frequencies, the polaritons exhibit different dispersion topologies. When different bias voltages are applied, the capacitance of the varactor diode loaded on the metasurface decreases (increases) as the applied voltage increases (decreases), leading to changes in the dispersion characteristics of the basic functional unit and the corresponding changes in the dispersion topology of the polaritons. When the applied voltages are V... C1 V C2 V C3 V C4 At that time, the dispersive topology of polaritons can be dynamically, in real time, and continuously switched between open ellipses, straight lines, hyperbolas, and circles.

[0039] To achieve the above functions, the reconfigurable metasurface in this embodiment is composed of Figure 2The basic functional units shown are constructed in a periodic extension manner in the xy two-dimensional plane. Specifically, the basic functional units of the metasurface, from top to bottom, are a first metal patch layer, a dielectric layer, and a second metal patch layer. The first metal patch layer is a centrally symmetrical complementary I-shaped geometric pattern with significant anisotropy. Here, complementary I-shape means that an I-shaped groove is removed from a complete metal plate, and the first metal patch layer of each of two adjacent units together forms a complementary I-shaped geometric pattern; the complementary I-shape of the first metal patch layer can also be a structure where the two horizontal lines of the I-shape are replaced with two arcs or arrows (i.e., double arrows), etc.; the second metal patch layer is a metal patch with a square ring removed. Each functional unit's second metal layer has a variable capacitance tube that is loaded across the square ring between the central square metal patch and the outer square ring metal patch; this embodiment In this embodiment, the internal square patches of the first and second metal layers are connected via metallized vias located at the center of the structural unit, and are respectively connected to the positive and negative terminals of the external circuit system to provide bias voltage; the square ring removed from the second metal layer of the basic functional unit can also be a circular ring (the inner diameter of the circular ring is larger than the diameter of the metallized via), and the position of the square / circular ring can also be in the first metal patch layer. In this embodiment, the purpose of placing the ring structure in the second metal patch layer is to avoid the influence of the physical structure of the varactor on the experimental test (near-field scanning needs to be performed 1-2 mm above the reconfigurable metasurface in the experimental test); Figure 1 In the reconfigurable metasurface structure shown, all basic functional units have the same geometric dimensions, and the capacitance value C loaded by each basic functional unit is... v By applying an external DC bias voltage V C Adjustable as needed; the dipole-fed antenna near the edge of the bottom region of the metasurface can be implemented using a tiny A-type connector, with the connector's inner core and outer shell connected to the first and second metal patch layers, respectively. The feeding location can also be other locations on the metasurface, such as the central region of the metasurface or the top region near the edge of the metasurface.

[0040] In this embodiment, the metal layer is made of copper foil with a thickness of 0.018 mm, and the dielectric layer is made of a material with a thickness of t. s The substrate is an F4B type plate with a thickness of 1.5mm, a dielectric constant of 2.2, and a loss tangent of 0.001. The period p of the basic functional unit is 8.5mm, and the structural parameters of the geometric pattern of the first metal patch layer are L. x =3.8mm,L y = 6.7mm, line width w is 0.3mm, the inner edge of the etched square ring of the second metal patch layer is l a It is 1.2mm thick, and the outer width is l. b =1.8mm, and the diameter of the metallized via connecting the first and second metal patch layers is 0.3mm.

[0041] Based on the above functional unit design, the basic functional units of the design were simulated using the commercial simulation software CST Microwave Studio. First, Figure 3 The colorimetric diagrams of the dispersion characteristics of the first band in the first Brillouin zone of the basic functional unit are presented under different applied capacitance values ​​when the polaritons propagate along the x and y directions, respectively. Figure 3 The right figures of (a) and (b) show the dispersion curves of the basic functional unit at several typical loaded capacitance values ​​of 0pF, 0.24pF, 0.30pF, and 0.52pF. x k y Let f represent the wave vectors of polaritons propagating along the x and y directions, respectively. It can be seen that, due to the in-plane anisotropy of the basic functional unit, polaritons propagating along the y direction exhibit higher eigenfrequency than those propagating along the x direction. In fact, for a given observation frequency f0, if f0 is lower than the cutoff frequencies along the two orthogonal x and y directions, polaritons can propagate in both directions, exhibiting an approximately circular or closed elliptical topological state. If f0 is higher than the cutoff frequency along the x direction but lower than the cutoff frequency along the y direction, then polaritons propagating along the x direction will be suppressed, exhibiting frequency-dependent topological states such as open ellipses, straight lines, and hyperbolas. As the applied capacitance value increases (decreases), the cutoff frequencies of polaritons propagating along both the x and y directions exhibit a monotonically decreasing (increasing) trend. The corresponding cutoff frequencies along the x-direction are 5.07 GHz, 4.65 GHz, 4.53 GHz, and 4.13 GHz; and along the y-direction are 8.00 GHz, 6.7 GHz, 6.35 GHz, and 5.33 GHz. This demonstrates that the dispersion characteristics of the basic functional unit can be controlled by changing the applied capacitance value. Therefore, with a fixed observation frequency, its relative relationship to the cutoff frequencies along the two orthogonal directions will change. Based on this, we can further flexibly design and implement reconfigurable topology transmission of polaritons.

[0042] Figure 4The momentum space isofrequency lines of the basic functional unit of this invention at an observation frequency of 6.1 GHz are given under typical loaded capacitance values ​​(a) 0 pF, (b) 0.24 pF, (c) 0.30 pF, and (d) 0.52 pF, respectively, corresponding to an open ellipse, a straight line, a hyperbola, and a circle. Here, as the loaded capacitance value increases from 0 pF to 0.30 pF, the isofrequency lines of the basic functional unit can achieve a continuous topological change from an open ellipse to an open hyperbola, accompanied by an increase in momentum. When the loaded capacitance value is 0.52 pF, the cutoff frequencies of the polaritons propagating along the x and y directions are both less than 6.1 GHz. At this time, there are no polaritons with a frequency of 6.1 GHz in the first band of the first Brillouin zone. We extracted the momentum space isofrequency lines of the polaritons in the second band of the first Brillouin zone, which correspond to the circle shown in Figure (d).

[0043] In this embodiment, sample processing and testing verification were carried out. Figure 5 The image shows photographs of (a) the top metal pattern and (b) the bottom metal base plate of the prototype. Figure 6 and Figure 7 Simulation and test results of the near-field electric field distribution of the reconfigurable metasurface with dynamically controlled electromagnetic polariton topological features in embodiments of the present invention are presented respectively. Observation Figure 6 The first row of images reveals that when the polariton dispersive topology switches between elliptical, linear, and hyperbolic shapes, the polariton wavefronts correspondingly exhibit outwardly divergent propagation, diffraction-free propagation, and inwardly converging propagation characteristics. By performing a Fourier transform on the near-field electric field distribution, we can obtain... Figure 6 The isofrequency lines in momentum space shown in the second row of images also exhibit a topological transport phenomenon, from an open ellipse to an open hyperbola and then to a circle, similar to... Figure 4 The momentum-space isofrequency lines of the basic functional units in the model are consistent. Furthermore, Figure 7 In the experimental test results of the medium sample, the near-field electric field distribution and the corresponding ground momentum space isofrequency lines are highly consistent with the simulation calculations.

[0044] The results above primarily use 6.1 GHz as the observation frequency. In reality, the reconfigurable metasurface in this embodiment can achieve topological switching of polaritons within a fixed frequency band (rather than being limited to a specific frequency) under different applied capacitance values. Figure 8 The relationship between the topology transmission region and the applied capacitance value and frequency in the embodiments of the present invention is given. Based on the electrically reconfigurable topology transmission of polaritons, we also further realized the functional design related to near-field electromagnetic wave modulation and manipulation. By applying different bias voltages, we can continuously realize the quasi-linear dispersive topology of polaritons over a wide frequency band, and the near-field electric field distribution of polaritons will correspondingly exhibit the characteristics of diffraction-free transmission. Figure 8The circles in the text mark a series of frequencies selected over a relatively wide frequency band for experimental verification of the diffraction-free transmission (field channelization) function; Reference Figure 9 Significant diffraction-free transmission can be observed at (a) 5.50 GHz, (b) 5.90 GHz, (c) 6.20 GHz and (d) 6.30 GHz, given different bias voltages.

[0045] Furthermore, we can continuously realize the open hyperbolic dispersion topology of polaritons over a relatively wide frequency band. Under this dispersion topology, the wavefront of the polaritons exhibits concave convergent propagation characteristics. When the polaritons propagate continuously from the metasurface into space outside the metasurface, negative refraction occurs at the interface between the metasurface and air, resulting in electromagnetic focusing. (Reference) Figure 10 Taking (a) 6.10 GHz, (b) 6.30 GHz, (c) 6.43 GHz and (d) 6.60 GHz as examples, we designed and realized the open hyperbolic dispersion topology of polaritons by changing the bias voltage and tested and characterized the near-field electric field distribution in a certain space in front of the reconfigurable metasurface. As expected, a significant focal point can be seen in all of them.

[0046] Furthermore, in this embodiment of the invention, we have also designed a planar electrically reconfigurable multifunctional polariton circuit. (See reference...) Figure 11 This paper presents a planar electrically reconfigurable multifunctional polariton circuit composed of two different regions as a practical example. The basic functional units within the same region have the same capacitance value, while the basic functional units in adjacent regions have different capacitance values. By spatially tailoring the dispersive topological combinations of polaritons in different regions and applying corresponding bias voltages to different regions of the metasurface, a circuit can be realized such as… Figure 12 The polariton beam splitter shown Figure 13 The polariton negative refraction shown and Figure 14 The polariton transport suppression and other functions shown, the capacitance values ​​loaded in different regions, and the momentum space isofrequency lines corresponding to the basic functional units are all within the range shown. Figures 12-14 The right side is presented, where V g This indicates the group velocity direction of the polaritons, which is also the main propagation direction in the incoming electric field distribution. In this embodiment of the invention, the above function is achieved through electronic control, which has the advantages of being easy to implement, having a large controllable range, being continuously controllable, having a high-speed response, and being able to switch in real time.

[0047] Some of the technical features of the above embodiments can be combined in more ways, such as planar electrically reconfigurable multifunctional polariton circuits with more regions, different frequencies, or other dispersion topologies. For the sake of brevity, not all possible cases of each technical feature in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0048] The above description is only a preferred embodiment of the present invention. The same structure can be scaled down or enlarged proportionally by means of the structural size, and the working frequency band of the reconfigurable metasurface with dynamically adjustable electromagnetic polariton topological characteristics can be flexibly designed by means of electrically adjustable devices operating at higher frequencies, and extended to millimeter wave band, terahertz band, etc.

[0049] Obviously, those skilled in the art, after understanding the content and principles of this invention, may make various modifications and changes in form and detail without departing from the principles and structure of this invention. Any simple equivalent changes and modifications made in accordance with the claims and the description of this invention should still fall within the scope of this patent.

Claims

1. A reconfigurable metasurface dynamically tuning topological features of electromagnetic polaritons, characterized in that, It is constructed by periodically extending the basic functional unit of the loaded varactor diode in a two-dimensional plane; the basic functional unit structure includes a first metal patch layer, a dielectric layer, and a second metal patch layer from top to bottom; the first and second metal patch layers are connected by a metallized via located at the center of the structural unit; The first metal patch layer is anisotropic. A ring-shaped metal structure centered on the metallized via is removed from the middle of the first or second metal patch layer. The varactor diode is connected across the metal patch areas inside and outside the ring formed after the ring-shaped metal structure is removed. The first and second metal patch layers are respectively connected to the positive and negative terminals of a DC voltage source.

2. The reconfigurable metasurface dynamically tuning electromagnetic polaritonic topological features of claim 1, wherein, The first metal patch layer is a centrally symmetrical complementary I-shaped geometric pattern; each half of the first metal patch layer of two adjacent units together forms an I-shaped groove; the two ends of the I-shaped groove are straight lines, arcs or arrows.

3. The reconfigurable metasurface with dynamically adjustable electromagnetic polariton topological features according to claim 1, characterized in that, The annular metal structure is removed from the middle of the second metal patch layer. The annulus is a square ring or a circular ring, and the inner ring side length / diameter of the square ring / circular ring is greater than the diameter of the metallized via.

4. The reconfigurable metasurface with dynamically adjustable electromagnetic polariton topological features according to claim 1, characterized in that, Metasurfaces support the generation and propagation of hyperbolic polaritons. By applying different bias voltages, reconfigurable topology transmission of polaritons can be achieved, and the dispersive topology of polaritons can be dynamically switched between open ellipse, straight line, hyperbola and circle.

5. The reconfigurable metasurface with dynamically adjustable electromagnetic polariton topological features according to claim 4, characterized in that, When the polariton dispersion topology switches between elliptic, linear, and hyperbolic forms, the surface wave front correspondingly exhibits the characteristics of outward divergence, no diffraction, and inward convergent propagation.

6. The reconfigurable metasurface with dynamically adjustable electromagnetic polariton topological features according to claim 1, characterized in that, It supports the design of planar reconfigurable multifunctional polariton circuits. The polariton circuit consists of multiple different regions. The basic functional units in each region have the same capacitance value, while the basic functional units in adjacent regions have different capacitance values. By spatially tailoring the dispersive topology combination of polaritons, corresponding bias voltages are applied to different regions of the metasurface to achieve polariton beam splitting, refraction modulation, and transmission suppression functions. Dynamic switching between functions can be achieved through electronic control.

7. The reconfigurable metasurface with dynamically adjustable electromagnetic polariton topological features according to claim 6, characterized in that, By applying different voltages to two adjacent regions 1 and 2 of the reconfigurable metasurface, the basic functional units in regions 1 and 2 exhibit quasi-linear and open elliptical topological features respectively under the corresponding loading capacitance values. When polaritons propagate from region 1 to region 2, the polariton splitting function can be realized at the interface between the two regions.

8. The reconfigurable metasurface with dynamically adjustable electromagnetic polariton topological features according to claim 6, characterized in that, Different voltages are applied to two adjacent regions 1 and 2 of the reconfigurable metasurface, causing the basic functional units in regions 1 and 2 to exhibit open elliptical and hyperbolic topological features, respectively, under the corresponding loading capacitance values. When polaritons propagate from region 1 to region 2, the polaritons propagating along the two mirror-symmetric directions in region 1 will undergo negative refraction at the interface between the two regions. If the applied voltage in region 1 is changed, so that the corresponding basic functional units exhibit quasi-linear and open elliptical features, respectively, the polaritons will undergo collimated refraction and positive refraction, respectively.

9. The reconfigurable metasurface with dynamically adjustable electromagnetic polariton topological features according to claim 6, characterized in that, By applying different voltages to two adjacent regions 1 and 2 of the reconfigurable metasurface, the basic functional units in regions 1 and 2 exhibit quasi-linear and circular topological features respectively under the corresponding loading capacitance values. When polaritons propagate from region 1 to region 2, the propagation of polaritons can be suppressed at the interface between the two regions.

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