An efficient electromagnetic waveguide based on topological chiral edge states

Abstract

The present invention discloses an efficient electromagnetic waveguide based on topological chiral edge states, belonging to the technical field of topological photonic crystals. The electromagnetic waveguide of the present invention includes two metal plates, a ferrite cylinder, and two dielectric waveguides partially covered with metal; the uniformly arranged ferrite cylinders form a unit cell array, which is divided into a first photonic crystal and a second photonic crystal, and magnetic fields with equal magnitudes and opposite directions are applied respectively, and topological edge states are formed at the interface between the first photonic crystal and the second photonic crystal. The present invention realizes efficient coupling between the excitation source and the topological waveguide by introducing a dielectric waveguide with partial metal attached, and finally realizes low-loss and efficient unidirectional transmission of electromagnetic signals along the topological waveguide. The topological electromagnetic waveguide of the present invention is immune to defects and impurities, and provides a new idea for the design of novel topological electromagnetic waveguides and the solution to the problem of efficient electromagnetic signal transmission.

Description

Technical Field

[0001] The present invention belongs to the technical field of topological photonic crystals, and particularly relates to an efficient electromagnetic waveguide based on topological chiral edge states. Background Art

[0002] As a new type of artificial electromagnetic material, a photonic crystal (PhC) can control the transmission of electromagnetic signals in the system by using its energy band characteristics. The PhC plays an important role in the design of photonic devices and has extremely high application value, such as novel photonic devices like PhC filters, PhC optical fibers, PhC isolators, and PhC circulators. However, the design of traditional PhC devices is limited by processing accuracy, and defects and impurities in the devices can cause strong backscattering and loss of electromagnetic signals, thus seriously affecting the device performance. With the continuous progress of modern science and research technologies, higher requirements have been put forward for aspects such as the performance indicators of PhC devices, which poses new challenges for the design of PhC devices.

[0003] Recently, the discovery of topological PhCs has provided a new solution to solve this problem. In recent years, due to the broad application prospects of topological PhCs, they have attracted extensive attention from researchers at home and abroad. Topological PhCs contain various novel physical properties and electromagnetic phenomena, which have promoted the research and development in this field. The topological phases of topological PhCs are usually distinguished by topological invariants. In a topological system, the topological invariant can be characterized by the Chern number. When two topological PhCs with different Chern numbers form an interface, according to the topological bulk-edge correspondence principle, topologically protected edge states with robust properties will be generated, and these edge states are immune to structural defects and impurities. So far, scientists have successively discovered the existence of topological edge states in PhC structures such as the optical quantum Hall effect, the optical quantum spin Hall effect, and the optical quantum valley Hall effect, enabling topological PhCs to achieve many results in the fields of topological electromagnetics and photonic integrated circuits and having broad application prospects in the future.

[0004] Currently, most of the research on topological edge states focuses on the application and promotion of robust transmission characteristics and the revelation of novel physical phenomena. However, when studying the transmission and application of topological PhCs, they usually need to be connected to traditional waveguide structures (such as microstrip lines, coplanar waveguides, dielectric waveguides). Therefore, it is very necessary to convert the guided waves supported by traditional waveguides into topological boundary modes supported by highly efficient topological PhC waveguides. However, the current research in this field is relatively scarce and urgently needs to be developed and improved. When using a point source as the excitation source, the coupling efficiency from the source to the topological edge state is extremely low and the loss is large, resulting in a problem of low overall transmission efficiency in the topological PhC system. Through analysis, it can be seen that it is particularly urgent to design a topological electromagnetic waveguide with high transmission efficiency, strong localization, and good unidirectionality. Summary of the Invention

[0005] The object of the present invention is to overcome the defects of the above-mentioned prior art and provide an efficient electromagnetic waveguide based on topological chiral edge states, which has the characteristics of switchable signal transmission direction, strong robustness, no backscattering, low loss, high-efficiency transmission, etc., so as to solve the problems of effective coupling and high-efficiency unidirectional transmission of electromagnetic signals.

[0006] The technical problems proposed by the present invention are solved as follows:

[0007] An efficient electromagnetic waveguide based on topological chiral edge states, having a 180° central rotationally symmetric structure, includes two metal plates, a ferrite cylinder, and two dielectric waveguides with partial metal claddings;

[0008] The upper metal plate and the lower metal plate are arranged in parallel; the ferrite cylinder is placed perpendicular to the metal plates and is connected to the upper metal plate and the lower metal plate at both ends respectively; the ferrite cylinders are evenly arranged at equal intervals of M×2N between the upper metal plate and the lower metal plate, and the edges of the ferrite cylinders located around are tangent to the edges of the metal plates, where M and N are positive integers and M>2N;

[0009] The dielectric waveguides with partial metal claddings are parallel to the long sides of the metal plates and extend from the outside of the central positions of the short sides of the metal plates into the metal plates respectively, and include a rectangular dielectric block and a trapezoidal dielectric block connected in sequence; the rectangular dielectric block and the trapezoidal dielectric block have the same thickness and are equal to the distance between the two metal plates; the rectangular dielectric block straddles the short side of the metal plate, and the trapezoidal dielectric block is located inside the two metal plates; the trapezoidal lower base of the trapezoidal dielectric block coincides with the rectangular short side of the rectangular dielectric block, and the rectangular long sides of the rectangular dielectric block are respectively tangent to two adjacent ferrite cylinders; the plane of the rectangular dielectric block connected to the two metal plates is covered with a metal layer, and metal thin plates extend from the two rectangular long sides of the rectangular dielectric block towards the trapezoidal dielectric block;

[0010] Every four adjacent ferrite cylinders form a primitive cell, and two sets of (M - 1)×(N - 1) primitive cell arrays closely arranged are formed on both sides of the connection line of the two dielectric waveguides with partial metal claddings, which are used as the first photonic crystal PhC1 and the second photonic crystal PhC2 respectively; the magnetic fields applied to the first photonic crystal PhC1 and the second photonic crystal PhC2 are equal in magnitude and opposite in direction.

[0011] Further, the radii of each ferrite cylinder in the first photonic crystal PhC1 and the second photonic crystal PhC2 are equal, and the ferrite material is selected as yttrium iron garnet (YIG) material.

[0012] Further, the rectangular dielectric block and the trapezoidal dielectric block are made of F4B material.

[0013] Further, the rectangular dielectric block and the corresponding metal layer form a rectangular waveguide, and the rectangular waveguide uses coaxial feeding.

[0014] Furthermore, the two rectangular waveguides serve as the input port and the output port respectively, both having a 50Ω impedance.

[0015] Furthermore, the magnitude of the applied magnetic field is H = 850 Oe, the lattice constant of the photonic crystal, i.e., the spacing a between adjacent ferrite cylinders, is 13 mm, and the diameter of the ferrite cylinder is 2r = 4 mm; the saturation magnetization of the ferrite material is 1850 Gs, the resonance linewidth is 15 Oe, the relative dielectric constant is 14, and the tangent loss is 0.0002.

[0016] Furthermore, the directions of the magnetic fields applied to the first photonic crystal PhC1 and the second photonic crystal PhC2 are downward and upward perpendicular to the metal plate respectively; the dielectric waveguide of the left - hand part of the metal cladding serves as the input port, and the dielectric waveguide of the right - hand part of the metal cladding serves as the output port; when the electromagnetic signal is input from the input port, the electromagnetic signal can bypass obstacles and defects and transmit to the output port. Conversely, when the electromagnetic signal is input from the output port, the electromagnetic signal cannot transmit to the input port;

[0017] By switching the directions of the bias magnetic fields applied to the first photonic crystal PhC1 and the second photonic crystal PhC2, the dielectric waveguide of the right - hand part of the metal cladding serves as the input port, and the dielectric waveguide of the left - hand part of the metal cladding serves as the output port; when the electromagnetic signal is input from the input port, the electromagnetic signal can bypass obstacles and defects and transmit to the output port. Conversely, when the electromagnetic signal is input from the output port, the electromagnetic signal cannot transmit to the input port.

[0018] Furthermore, by regulating the direction of the applied magnetic field, the non - reciprocal transmission and isolation characteristics of the electromagnetic waveguide described in the present invention can be achieved.

[0019] Based on the polarization characteristics of the PhC waveguide mode and combined with the traditional waveguide mode, the present invention provides an efficient electromagnetic waveguide based on topological chiral states. The dielectric waveguide in the electromagnetic waveguide described in the present invention is applicable to the microwave band and has a 50Ω characteristic impedance. Its tapered structure serves as a smooth transition section for the guided wave to be converted into the topological boundary state to match the modes and impedances of the dielectric waveguide and the topological waveguide. Through end - to - end coupling, the effective conversion of the electromagnetic signal from the guided - wave mode to the topological boundary mode can be conveniently realized, achieving a topological electromagnetic waveguide with high - efficiency coupling and transmission. The numerical simulations of the S - parameters and the near - field distribution show that the proposed structure has a high transmission efficiency. This topologically protected electromagnetic waveguide has good robustness, its boundary state is very stable, the transmission characteristics are not affected by defects or obstacles, and it has a high tolerance for fabrication errors, which can significantly reduce the transmission loss. Therefore, the present invention opens up a new way for the development of topological unidirectional electromagnetic waveguides with high coupling efficiency, high - efficiency transmission, and low loss.

[0020] The beneficial effects of the present invention are:

[0021] (1) The electromagnetic wave to structure design of the present invention is novel, and a firm and stable structure is formed among the metal plate, the ferrite, and the dielectric waveguide. The ferrite material preparation technology is mature and easy to manufacture, ensuring that the topological waveguide structure has characteristics such as high efficiency, high isolation, low loss, reliable mechanical and electromagnetic properties, etc.

[0022] (2) Since the electromagnetic signal propagates at the interface of two different photonic crystals, the topological electromagnetic waveguide of the present invention has good locality for the electromagnetic signal, can reduce the scattering of the electromagnetic signal into the photonic crystal, and improve the transmission efficiency of the waveguide. The backscattering is strongly suppressed, and robust unidirectional transmission can be achieved.

[0023] (3) In the communication system, the topological electromagnetic waveguide of the present invention realizes the non-reciprocal transmission and directional isolation characteristics of the electromagnetic signal, and has great application prospects in aspects such as protecting the signal source, regulating the directional transmission of the signal, and exploring novel physical phenomena of topological electromagnetics. Description of the Drawings

[0024] Figure 1 Schematic diagram of the internal structure of the high-efficiency electromagnetic waveguide described in the embodiment;

[0025] Figure 2 Schematic diagram of the projected energy band structure of the high-efficiency electromagnetic waveguide described in the embodiment;

[0026] Figure 3 Schematic diagrams of the electric field intensity distribution and S-parameter curves when the electromagnetic signal enters the topological electromagnetic waveguide from port port1 and port port2 respectively at a frequency of 13.5 GHz for the high-efficiency electromagnetic waveguide described in the embodiment;

[0027] Figure 4 Schematic diagrams of the electric field distribution and S-parameter curves when the electromagnetic signal is incident from port port1 at a frequency of 13.5 GHz for the high-efficiency electromagnetic waveguide described in the embodiment when there is a metal baffle (obstacle);

[0028] Figure 5 Schematic diagrams of the electric field distribution and S-parameter curves when the electromagnetic signal is incident from port port1 at a frequency of 13.5 GHz for the high-efficiency electromagnetic waveguide described in the embodiment when there is a metal post (defect);

[0029] Figure 6 Comparison diagram of S-parameter curves in three different cases when the electromagnetic signal is incident from port port1 for the high-efficiency electromagnetic waveguide described in the embodiment. The three different cases are the topological electromagnetic waveguide without perturbation (conventional), the topological electromagnetic waveguide with a metal baffle (obstacle), and the topological electromagnetic waveguide with a metal post (defect). Detailed Embodiment

[0030] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0031] This embodiment provides an efficient electromagnetic waveguide based on topological chiral edge states, as Figure 1 shown, having a 180° central rotation symmetry structure, including two metal plates, a ferrite cylinder, and two partially metal-coated dielectric waveguides.

[0032] The upper metal plate (not drawn in Figure 1 for clarity of the internal structure) and the lower metal plate are arranged in parallel; the ferrite cylinder is placed perpendicular to the metal plates and is connected to the upper metal plate and the lower metal plate at both ends respectively; the ferrite cylinders are evenly arranged at equal intervals of M×2N between the upper metal plate and the lower metal plate, and the edges of the ferrite cylinders located around are tangent to the edges of the metal plates, where M and N are positive integers and M > 2N.

[0033] The partially metal-coated dielectric waveguides are parallel to the long sides of the metal plates and extend from the outside of the central positions of the short sides of the metal plates into the metal plates respectively, including a rectangular dielectric block and a trapezoidal dielectric block connected in sequence; the rectangular dielectric block and the trapezoidal dielectric block have the same thickness and are equal to the distance between the two metal plates; the rectangular dielectric block straddles the short side of the metal plate, and the trapezoidal dielectric block is located inside the two metal plates; the trapezoidal lower base of the trapezoidal dielectric block coincides with the rectangular short side of the rectangular dielectric block, and the rectangular long sides of the rectangular dielectric block are respectively tangent to two adjacent ferrite cylinders; the plane of the rectangular dielectric block connected to the two metal plates is coated with a metal layer, and metal thin plates extend along the two rectangular long sides of the rectangular dielectric block towards the trapezoidal dielectric block.

[0034] Every four adjacent ferrite cylinders form a primitive cell, and two sets of (M - 1)×(N - 1) primitive cell arrays closely arranged are formed on both sides of the connection line of the two partially metal-coated dielectric waveguides, serving as the first photonic crystal PhC1 and the second photonic crystal PhC2 respectively.

[0035] Magnetic fields applied to the first photonic crystal PhC1 and the second photonic crystal PhC2 are equal in magnitude and opposite in direction.

[0036] The radius of each ferrite cylinder in the first photonic crystal PhC1 and the second photonic crystal PhC2 is equal, and the ferrite material is selected as yttrium iron garnet (YIG) material. The processing technology of the ferrite cylinder is convenient and easy to fabricate.

[0037] The rectangular dielectric block and the trapezoidal dielectric block are made of F4B material.

[0038] The dielectric waveguide is fed coaxially.

[0039] Two dielectric waveguides with partial metal claddings serve as the input port and the output port respectively, both having a 50Ω impedance. As a smooth transition section for guiding wave to convert into topological boundary states, it matches the modes and impedances of the dielectric waveguide and the topological waveguide. One side of the dielectric waveguide with partial metal cladding provides a traditional guiding wave mode, and the tapered part of the dielectric waveguide can smoothly transition the traditional guiding wave mode to the boundary state mode of the topological waveguide, achieving an efficient conversion from the traditional guiding wave mode to the topological mode, with characteristics such as low loss and efficient transmission.

[0040] In this embodiment, the structural dimensions of the dielectric waveguide are W = 9mm, W 1 = 0.5mm, L o = 39mm, L = 65mm, L 1 = 8mm, having broadband characteristics. Through end-to-end coupling, electromagnetic signals can be efficiently converted from the guiding wave mode to the topological boundary mode, realizing efficient transmission of electromagnetic waves.

[0041] Taking the center of the ferrite cylinder array as the origin and the plane where the metal plate is located as the xoy plane, the x-axis and the y-axis are parallel to the long side and the short side of the metal plate respectively. The first photonic crystal PhC1 and the second photonic crystal PhC2 are symmetrically placed on both sides of the y = 0 interface, and different directions of magnetic fields are applied to each side of the PhC to provide topological chiral electromagnetic modes with co-propagation, and the rotation directions of the electromagnetic modes on both sides are opposite; the boundary states provided by each side of the PhC are transmitted in the channel formed by the two interfaces to enhance the robustness of the transmission channel, and the electromagnetic energy can be well localized in the channel for transmission.

[0042] By applying magnetic fields with equal magnitudes and opposite directions to the first photonic crystal PhC1 and the second photonic crystal PhC2, the time-reversal symmetry is broken. According to the bulk-edge correspondence principle, topological boundary states will exist at the y = 0 interface. In this embodiment, the magnitude of the magnetic field is H = 850 Oe, the ferrite cylinders are arranged in a square lattice, the lattice constant, i.e., the spacing a between adjacent ferrite cylinders, is 13mm, and the diameter of the cylinder is 2r = 4mm; the saturation magnetization of the ferrite material is 1850 Gs, the resonance linewidth is 15 Oe, the relative dielectric constant is 14, and the tangent loss is 0.0002. Utilizing the coupling effect between the traditional guiding wave mode and the topological chiral boundary state to achieve high-efficiency unidirectional transmission with topological characteristics and high reverse isolation.

[0043] The first photonic crystal PhC1 and the second photonic crystal PhC2 support topological boundary modes with the same propagation direction within the same frequency range. When an electromagnetic signal is input from the left port, the electromagnetic energy is output from the right port; however, when an electromagnetic signal is input from the right port, the transmission of electromagnetic energy in the channel is prohibited, realizing non-reciprocal transmission and directional isolation of electromagnetic waves. The non-reciprocal transmission and isolation characteristics in different directions can be achieved by regulating the direction of the magnetic field.

[0044] The topological efficient electromagnetic waveguide described in this embodiment has defect immunity characteristics and is not affected by defects and discontinuous structures. As Figure 1 shown, the directions of the magnetic fields applied to PhC1 and PhC2 are downward and upward perpendicular to the metal plate, respectively; within the same frequency range, when an electromagnetic signal is input from the port1 port (left port), if there are obstacles or defects in the waveguide, the chiral edge states in the topological waveguide can bypass the obstacles (metal baffles) and defects (missing metal posts) and continue to transmit forward robustly. Under the introduction of perturbations and normal conditions, it has the same high-efficiency transmission and non-backscattering characteristics, and the transmission efficiency and return loss are almost the same in the three cases of input without perturbation (normal), adding a metal baffle (obstacle), and a metal post (defect) from the port1 port (left port). That is, when an electromagnetic signal is input from the left port of the topological electromagnetic waveguide, the electromagnetic signal can be transmitted to the right port robustly; due to the unidirectionality of the topological chiral edge state, when an electromagnetic signal is input from the port2 port (right port) of the topological electromagnetic waveguide, the electromagnetic signal cannot be transmitted to the port1 port (left port), realizing the unidirectional transmission and isolation characteristics of the electromagnetic signal. When the directions of the bias magnetic fields applied to PhC1 and PhC2 are switched, when an electromagnetic signal is input from the port2 port (right port) of the topological electromagnetic waveguide, the electromagnetic signal can be transmitted to the port1 port (left port) robustly; due to the unidirectionality of the topological chiral edge state, when an electromagnetic signal is input from the port1 port (left port) of the topological electromagnetic waveguide, the electromagnetic signal cannot be transmitted to the port2 port (right port). Therefore, this electromagnetic waveguide has the characteristics of topologically protected high-efficiency unidirectional transmission and reverse isolation.

[0045] Figure 2 Schematic diagram of the projected energy band structure of the efficient electromagnetic waveguide described in the embodiment. Taking the boundary between PhC1 and PhC2 as the reference, 10 unit cells are taken above and below respectively, and these two types of PhC are placed together, and the projected energy bands of the two types of PhC along the interface direction are calculated by the supercell calculation method to determine the edge states. The shaded area marks the bandgap range - the frequency range of the topological chiral edge state, which is represented by two circular dotted lines. To more vividly characterize the topological chiral edge state, the right figure shows the electric field distributions of the two topological chiral edge states respectively. One is the even mode and the other is the odd mode at the interface of y = 0. Right 1 gives the eigenmode with a frequency of 13.8 GHz and a wave vector of 0.8(π / a), and right 2 gives the eigenmode with a frequency of 13.6 GHz and a wave vector of 0.6(π / a), where the black dotted line is the mirror plane; the even or odd waveguide modes in the edge can be selectively excited by a polarization source. In this example, the even waveguide mode is selectively excited. It can be seen from the figure that the even (or odd) waveguide mode only exists at k x < 0 (k xIn the wave vector range greater than 0, its surface only supports unidirectional chiral edge states; when the direction of the externally applied magnetic field changes, there are unidirectional edge states with opposite directions.

[0046] To intuitively illustrate the transmission characteristics of electromagnetic signals, the S-parameter curves of the topological electromagnetic waveguide described in this embodiment and the field strength distribution of Ez when electromagnetic signals are input from different ports are numerically simulated using the commercial software CST Microwave Studio. Figures 3 to 6 As shown in the figure, the working principle is more clearly demonstrated, where the arrows indicate the directions of input and output of electromagnetic signals. The two terminals of the dielectric waveguide form two ports, port1 and port2. The propagation direction of the topological chiral edge state is related to the bias direction of the externally applied magnetic field. When electromagnetic waves are input from port1 or port2 respectively, their propagation situations are respectively shown in Figures 4 to 6 as follows.

[0047] Figure 3 The figure shows the changes in the S-parameter curves when electromagnetic waves are input from port1 and port2 respectively. It can be seen from the figure that at the same frequency of 13.5 GHz, the two cases have an extremely high isolation ratio and opposite transmission characteristics. When the electromagnetic signal is input from port1, the tapered transition from the dielectric waveguide can well transition the guided wave mode to the topological chiral edge state, and almost all electromagnetic signals can be well transmitted along the interface to port2; it can be seen from the S-parameter curve that the return loss is greater than 15 dB and the insertion loss is less than 2 dB; when the electromagnetic signal is input from port2, the electromagnetic signal is scattered into the PhC and dissipated, and no electromagnetic signal is transmitted to port2. It can be seen from the S-parameter curve that the return loss is greater than 15 dB and the insertion loss is less than 45 dB; the return losses of the two are almost the same, with the characteristic of no backscattering. This indicates that the topological electromagnetic waveguide has excellent characteristics of low insertion loss, high-efficiency unidirectional transmission, and reverse isolation.

[0048] The most prominent feature of the topological electromagnetic waveguide is its immunity to perturbations and defects. To verify the immunity of the proposed high-efficiency topological electromagnetic waveguide to structural defects, we introduce two different structural defects. One is to introduce a metal baffle (obstacle) into the waveguide, and the other is to introduce a metal post (defect), as shown in Figure 4 and Figure 5 respectively. They are the electric field distribution and S-parameter curves at 13.8 GHz when the electromagnetic signal is input from port1. The chiral edge state propagating in the waveguide can well bypass the metal baffle (obstacle) and the metal post (defect) and continue to propagate forward. It can be seen from the S-parameter curve that the transmission efficiency and return loss in the two cases do not change significantly compared with those without perturbation in Figure 2 . Therefore, for the electromagnetic signal input from port1, most of the electromagnetic signals on the topological electromagnetic waveguide can be transmitted to port2.Figure 2 Similarly, when an electromagnetic signal is input from port2, since the chiral edge state does not support reverse transmission, no electromagnetic signal is transmitted to port1 for output in the topological electromagnetic waveguide. Even in the presence of perturbations, an efficient topological one-way electromagnetic waveguide can be achieved.

[0049] To more clearly show the transmission performance in three different cases, Figure 6 It shows the variation of the S-parameter curve when an electromagnetic wave is input from port1 under the conditions of no perturbation (conventional), a metal baffle (obstacle), and a metal post (defect). It can be seen from the S-parameter curve that within the same frequency range, the electromagnetic wave has the same transmission characteristics, and the transmission efficiency and return loss are almost the same in the three cases. It can be seen that the efficient electromagnetic waveguide has strong robustness and the characteristics of topologically protected efficient one-way transmission and reverse isolation. When the direction of the bias magnetic field applied to the two regions of the PhC is switched, the one-way transmission and reverse isolation characteristics of the electromagnetic wave are exactly the opposite of the above situation.

[0050] The efficient electromagnetic waveguide based on the topological chiral edge state in this embodiment uses a dielectric (F4B) waveguide with some attached metal to achieve the coupling and efficient conversion of transmission modes. This waveguide has characteristics such as high transmission efficiency and wideband. The topological chiral edge state can achieve efficient transmission at the boundary of two PhCs. The excellent performance of this efficient topological electromagnetic waveguide has important application prospects in the millimeter-wave, terahertz, and optical frequency bands, including fault-tolerant slow-light systems, isolators, high-Q channel non-reciprocal add / drop filters, and non-reciprocal all-pass filters. It is beneficial to design topological electromagnetic devices with efficient transmission, and to a large extent, it avoids the influence of processing defects on the device performance. Through the verification of the embodiment, under different perturbations, when the electromagnetic wave is input from different ports, it shows good one-way transmission and isolation characteristics, indicating that the proposed efficient topological electromagnetic waveguide structure has characteristics such as no backscattering, strong robustness, switchable transmission direction, high transmission efficiency and isolation degree, and low loss.

[0051] The above is a preferred embodiment of the present invention and does not limit the present invention. All modifications and improvements made within the principle and spirit of the present invention are within the protection scope of the present invention.

Claims

1. An efficient electromagnetic waveguide based on topological chiral edge states, characterized in that, it has a 180° central rotation symmetry structure, and includes two metal plates, a ferrite cylinder, and two partially metal-clad dielectric waveguides; The upper metal plate and the lower metal plate are arranged in parallel; the ferrite cylinder is placed perpendicular to the metal plates and is connected to the upper metal plate and the lower metal plate at both ends respectively; the ferrite cylinders are evenly arranged at equal intervals of M×2N between the upper metal plate and the lower metal plate, and the edges of the ferrite cylinders located around are tangent to the edges of the metal plates, where M and N are positive integers and M>2N; The partially metal-clad dielectric waveguides are parallel to the long sides of the metal plates and extend from the outside of the central position of the short sides of the metal plates into the metal plates respectively, and include a rectangular dielectric block and a trapezoidal dielectric block connected in sequence; the rectangular dielectric block and the trapezoidal dielectric block have the same thickness and are equal to the distance between the two metal plates; the rectangular dielectric block straddles the short side of the metal plate, and the trapezoidal dielectric block is located inside the two metal plates; the trapezoidal lower base of the trapezoidal dielectric block coincides with the rectangular short side of the rectangular dielectric block, and the rectangular long sides of the rectangular dielectric block are tangent to two adjacent ferrite cylinders respectively; the plane of the rectangular dielectric block connected to the two metal plates is covered with a metal layer, and metal thin plates extend along the two rectangular long sides of the rectangular dielectric block towards the trapezoidal dielectric block; Every four adjacent ferrite cylinders form a primitive cell, and two groups of (M - 1)×(N - 1) closely arranged primitive cell arrays are formed on both sides of the connection line of the two partially metal-clad dielectric waveguides, which are used as the first photonic crystal PhC1 and the second photonic crystal PhC2 respectively; the magnetic fields applied to the first photonic crystal PhC1 and the second photonic crystal PhC2 are equal in magnitude and opposite in direction; The directions of the magnetic fields applied to the first photonic crystal PhC1 and the second photonic crystal PhC2 are perpendicular to the metal plates downward and upward respectively; the left partially metal-clad dielectric waveguide is used as the input port, and the right partially metal-clad dielectric waveguide is used as the output port; when an electromagnetic signal is input from the input port, the electromagnetic signal can bypass obstacles and defects and transmit to the output port, and vice versa, when an electromagnetic signal is input from the output port, the electromagnetic signal cannot be transmitted to the input port; By switching the directions of the bias magnetic fields applied to the first photonic crystal PhC1 and the second photonic crystal PhC2, the right partially metal-clad dielectric waveguide is used as the input port, and the left partially metal-clad dielectric waveguide is used as the output port; when an electromagnetic signal is input from the input port, the electromagnetic signal can bypass obstacles and defects and transmit to the output port, and vice versa, when an electromagnetic signal is input from the output port, the electromagnetic signal cannot be transmitted to the input port.

2. The efficient electromagnetic waveguide based on topological chiral edge states according to claim 1, characterized in that, the radii of each ferrite cylinder in the first photonic crystal PhC1 and the second photonic crystal PhC2 are equal, and the ferrite material is selected as yttrium iron garnet type material.

3. The efficient electromagnetic waveguide based on topological chiral edge states according to claim 1, characterized in that, the rectangular dielectric block and the trapezoidal dielectric block are made of F4B material.

4. The efficient electromagnetic waveguide based on topological chiral edge states according to claim 1, characterized in that, A rectangular dielectric block and the corresponding metal layer form a rectangular waveguide, and the rectangular waveguide is fed coaxially.

5. The high-efficiency electromagnetic waveguide based on topological chiral edge states according to claim 4, wherein, Two rectangular waveguides are respectively used as the input port and the output port, both having a 50Ω impedance.

6. The high-efficiency electromagnetic waveguide based on topological chiral edge states according to claim 1, wherein, The magnitude of the applied magnetic field is H = 850 Oe, the lattice constant of the photonic crystal, i.e., the spacing a between adjacent ferrite cylinders, is 13 mm, and the diameter of the ferrite cylinder is 2r = 4 mm; the saturation magnetization of the ferrite material is 1850 Gs, the resonance linewidth is 15 Oe, the relative dielectric constant is 14, and the tangent loss is 0.0002.

7. The high-efficiency electromagnetic waveguide based on topological chiral edge states according to claim 1, wherein, By adjusting the direction of the applied magnetic field, the non-reciprocal transmission and isolation characteristics of the electromagnetic waveguide can be achieved.

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