Different-plane double-resonant ring and two-dimensional array and three-dimensional array thereof

Abstract

The utility model relates to a different-plane double-resonant ring and a two-dimensional array and a three-dimensional array thereof. The different-plane double-resonant ring comprises a first metal wire (101) and a second metal wire (102), the first metal wire (101) and the second metal wire (102) are wound on different surfaces to form double resonant rings; the length of the first metal wire (101) is equal to that of the second metal wire (102); and a first opening (201) and a second opening (202) are arranged below the double resonant rings. According to the utility model, the different-plane double-resonant-ring structure is used as a metamaterial structure unit, and a novel electromagnetic resonance mode-topology resonance with strong robustness is induced to be generated by using the phase difference accumulated when current passes through different geometric paths. According to the utility model, the two-dimensional array and the three-dimensional array have no frequency deviation phenomenon in electromagnetic response at a designed topological resonance frequency point under the condition that electromagnetic waves are incident from-89 degrees to 89 degrees; under the vertical and horizontal polarization modes, the electromagnetic response characteristics of the designed topological resonance frequency point are kept unchanged, and the method has a good market application prospect.

Description

Technical Field

[0001] The utility model belongs to the field of metamaterials, and particularly relates to a heterogeneous double resonant ring and a two-dimensional array and a three-dimensional array thereof. Background Art

[0002] Based on the interaction generated by the electric field or magnetic field, the electromagnetic resonance modes in metamaterials can be divided into electric resonance and magnetic resonance. To induce electric resonance, the simplest method is to use a wire as a resonator, which is placed parallel to the direction of the electric field. In this case, the free electrons in the wire will be driven by the electric field to produce coherent oscillations, resulting in electric resonance behavior. For magnetic resonance, the most commonly used structure is the split ring resonator (SRR). The basic principle is that when the magnetic field direction is perpendicular to the plane of the SRR, the oscillating magnetic field induces a circular current in the SRR, which can be considered as a magnetic moment. Such a magnetic moment will lead to magnetic resonance behavior at a specific frequency. Both the electric resonance and the magnetic resonance of electromagnetic waves strongly depend on the incident angle and polarization mode of the electromagnetic wave. Once the incident angle or polarization mode of the electromagnetic wave changes, the electromagnetic wave response of the metamaterial will also change, resulting in a drastic deviation from the original design of electromagnetic wave manipulation performance.

[0003] In the complex environment of actual scenes, the angle and polarization mode of the incident electromagnetic wave are usually difficult to determine. For example, the surface of the frequency selective antenna cover is usually arc-shaped, and the angle and polarization mode of the incident electromagnetic wave cannot be determined. Traditional electromagnetic metamaterial antenna covers designed based on electric resonance and magnetic resonance will exhibit different electromagnetic response characteristics. Specifically, their resonant frequency, bandwidth and reflection / transmission ratio will change with the change of the incident angle and polarization mode, resulting in the radar cover's stealth performance being reduced or even failing. Therefore, improving the angle stability and polarization stability of the electromagnetic response of metamaterials has been a hot issue that scholars at home and abroad have been paying attention to.

[0004] In recent years, scientists have proposed many methods to improve the electromagnetic response angle and polarization performance of metamaterials. According to the theory proposed by Munk, using highly symmetrical geometric structures as units of metamaterials usually has better incident angle and polarization mode stability. However, the angle range of almost all proposed metamaterials is usually limited to ±60° or single polarization mode, and dual-polarization metamaterials with an angle stability greater than 60° are rarely reported. Therefore, how to make metamaterials have good electromagnetic response characteristics while further improving the angle stability and polarization stability has always been a problem that needs to be solved. Summary of the invention

[0005] The technical problem to be solved by the utility model is to provide a dyad resonant ring and a two-dimensional array and a three-dimensional array thereof, which can effectively solve the problem that the electromagnetic response of metamaterials varies greatly at different angles and polarizations, improve the functional indicators of metamaterials, and expand their application scenarios.

[0006] The utility model provides an eccentric double resonant ring, comprising a first metal wire and a second metal wire; the first metal wire and the second metal wire are wound on eccentric surfaces to form a double resonant ring; the first metal wire and the second metal wire are equal in length; a first opening and a second opening are arranged below the double resonant ring.

[0007] Each metal wire has a diameter of d and is wound on different surfaces to form a nearly circular shape with a deviation distance of h in the z direction. The radius of the shortest end away from the center circle is Rr, and the radius of the longest end is R+r. There is an opening symmetrical with the y axis at the bottom. The opening length of the distance between the two metal wires is x, and the distance between two adjacent structural units is α. This array of different-surface double resonant ring structural units arranged in a certain manner becomes a metamaterial with a special electromagnetic response. This is because the accumulated phase difference (geometric phase difference) when the current passes through two different geometric paths induces a new type of electromagnetic resonance mode with strong robustness - topological resonance. It is different from the common electric resonance and magnetic resonance in ordinary metamaterials. The resonant frequency of topological resonance depends only on the geometric phase difference, and does not strictly depend on the geometric parameters and arrangement of the structural unit. In the structural unit of the utility model, its geometric phase difference is non-zero, which will cause interference absorption of electromagnetic waves, so a topological resonance peak appears; the smaller the opening length x value of the distance between the two metal wires, the closer the geometric phase difference is to 180°, and the more stable the topological resonance peak when electromagnetic waves are incident at different angles.

[0008] Preferably, the diameter d of the metal wire is 0.02-1 mm, the opening x is 0-3 mm, the center circle radius R is 1-10 mm, r is 0.2-0.8 mm, and the distance α between two adjacent structural units is 5-25 mm.

[0009] Preferably, the first metal wire and the second metal wire are made of one or more of silver, gold, aluminum, iron, tin and copper.

[0010] Preferably, the cross-sectional shapes of the first metal wire and the second metal wire are one or more of circular, square, rectangular, triangular and polygonal.

[0011] The utility model also provides a two-dimensional array, which takes the unequal-planar double resonant rings as structural units and is arranged into an array.

[0012] Preferably, the arrangement includes square, rectangular, centered cubic, rhombus, honeycomb hexagonal or any combination of the foregoing arrangements.

[0013] The utility model also provides a three-dimensional array, and the two-dimensional array is cascaded to form a three-dimensional array.

[0014] Beneficial effects

[0015] (1) The skew-coplanar dual resonant ring structure of the utility model is used as a metamaterial structural unit. It utilizes the accumulated phase difference when the current passes through different geometric paths to induce a new electromagnetic resonance mode with strong robustness, namely, topological resonance. Its strong robustness, that is, the position of the resonance frequency depends on the geometric phase difference, and is not strictly dependent on the geometric parameters and arrangement of the structural unit, is of great significance for practical applications.

[0016] (2) Under the condition of electromagnetic wave incident angle of -89° to 89°, the electromagnetic response of the two-dimensional array and the three-dimensional array of the utility model has no frequency shift phenomenon at the designed topological resonance frequency; under the vertical and horizontal polarization modes, the electromagnetic response characteristics of the designed topological resonance frequency remain unchanged, which has good market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of the utility model's unequal-plane double resonant ring;

[0018] Figure 2 It is the main view, front view and side view of the unequal-plane double resonant ring of the utility model; wherein 1 is a metal wire, and 2 is a center circle (auxiliary line);

[0019] Figure 3 is a schematic diagram of a two-dimensional array of eccentric double resonant rings arranged in a square in Example 1;

[0020] Figure 4 1 is a diagram of the simulated transmission coefficient result of the two-dimensional array in Example 1, wherein (a) and (b) are diagrams showing the transmission coefficient variation with frequency for vertical polarization and horizontal polarization at different incident angles, and (c) and (d) are diagrams showing the variation of topological resonance with incident angle (-89° to 89°) for vertical polarization and horizontal polarization, respectively;

[0021] Figure 5 is a schematic diagram of the center squares of the eccentric double resonant rings in Example 2 arranged in a two-dimensional array;

[0022] Figure 6 1 is a diagram of the simulated transmission coefficient result of the two-dimensional array in Example 2, wherein (a) and (b) are diagrams showing the transmission coefficient variation with frequency for vertical polarization and horizontal polarization at different incident angles, and (c) and (d) are diagrams showing the variation of topological resonance with incident angle (-89° to 89°) for vertical polarization and horizontal polarization, respectively;

[0023] Figure 7 is a schematic diagram of a two-dimensional array of eccentric double resonant rings arranged in a square in Example 3;

[0024] Figure 8: is a simulation transmission coefficient result diagram of the two-dimensional array in Example 3, wherein (a) and (b) are transmission coefficients of vertical polarization and horizontal polarization at different angles of incidence versus frequency, respectively, and (c) and (d) are topological resonances of vertical polarization and horizontal polarization versus incident angle (-89° to 89°), respectively;

[0025] Figure 9 is a schematic diagram of a three-dimensional array composed of skew double resonant rings in Example 4;

[0026] Figure 10 It is a simulation transmission coefficient result diagram of the three-dimensional array in Example 4, with an angle of 0 to 80° and a step size of 10°, wherein (a) and (b) are diagrams showing the transmission coefficient variation with frequency for vertical polarization and horizontal polarization at different incident angles, respectively. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

[0028] Example 1

[0029] like Figure 1 and Figure 2 As shown in FIG. 1 , a skew double resonant ring structure is designed, including a first metal wire 101 and a second metal wire 102; the first metal wire 101 and the second metal wire 102 are wound on skew surfaces to form a double resonant ring; the first metal wire 101 and the second metal wire 102 are equal in length; a first opening 201 and a second opening 202 are provided below the double resonant ring. The two-dimensional metamaterial is arranged in a square arrangement to form an ideal infinite size and laid flat in the xoy plane, as shown in FIG. Figure 3 As shown. Among them, the center circle radius R = 4mm, r is 0.4mm, the opening distance is x = 0.5mm, the cross-sectional shape of the metal wire is circular, the diameter is d = 0.2mm, the material is a perfect conductor (PEC), and the distance between adjacent units is a = 10mm. Through the calculation of electromagnetic simulation software, the negative direction of the z-axis is set as the wave vector direction, and the boundary condition is set as unit cell. The topological resonance of the designed metamaterial under the incident electromagnetic wave of -89° to 89° and vertical and horizontal polarization modes is obtained, as shown Figure 4 As shown, the topological resonance frequency is stable at 6.11 GHz under -89° to 89° incidence and both polarization modes.

[0030] Example 2

[0031] The same eccentric double resonant ring structure as in Example 1 is used, and arranged in a central square arrangement to form an ideal infinite two-dimensional metamaterial, which is laid flat in the xoy plane, such as Figure 5 As shown. Among them, the center circle radius R = 4mm, r is 0.4mm, the opening distance is x = 1mm, the cross-sectional shape of the metal wire is circular, the diameter is d = 0.2mm, the material is a perfect conductor (PEC), and the distance between adjacent units is a = 14mm. Through the calculation of electromagnetic simulation software, the negative direction of the z-axis is set as the wave vector direction, and the boundary condition is set as unit cell. The topological resonance of the designed metamaterial under the electromagnetic wave incident at -89° to 89° and vertical and horizontal polarization modes is obtained, as shown Figure 6 As shown, the topological resonance frequency is stable at 6.35 GHz under -89° to 89° incidence and both polarization modes.

[0032] Embodiment 3:

[0033] The same eccentric double resonant ring structure as in Example 1 is used, and arranged in a square manner to form an ideal infinite two-dimensional metamaterial, which is laid flat in the xoy plane, such as Figure 7 As shown. Among them, the center circle radius R = 4mm, r is 0.4mm, the opening distance is x = 0mm, the cross-sectional shape of the metal wire is circular, the diameter is d = 0.2mm, the material is metallic silver, and the distance between adjacent units is a = 10mm. Through the calculation of electromagnetic simulation software, the negative direction of the z-axis is set as the wave vector direction, and the boundary condition is set to unitcell. The topological resonance of the designed metamaterial under the electromagnetic wave incident at -89° to 89° and vertical and horizontal polarization modes is obtained, as shown Figure 8 As shown, the topological resonance frequency is stable at 6.00 GHz at -89° to 89° incidence and in both polarization modes.

[0034] Embodiment 4:

[0035] The same eccentric double resonant ring structure as in Example 1 is used, arranged in a square arrangement to form an ideal infinite two-dimensional metamaterial, and cascaded in the z direction to form a three-dimensional metamaterial, such as Figure 9 As shown. Among them, the center circle radius R = 4mm, r is 0.4mm, the opening distance is x = 0mm, the cross-sectional shape of the metal wire is circular, the diameter is d = 0.2mm, the material is metal copper, and the distance between adjacent units is a = 10mm. Through the calculation of electromagnetic simulation software, the negative direction of the z axis is set as the wave vector direction, and the boundary condition is set as unit cell. The topological resonance of the designed metamaterial under the electromagnetic wave incident at -89° to 89° and vertical and horizontal polarization modes is obtained, as shown Figure 10 As shown, the topological resonance frequency is stable at 5.96 GHz under -89° to 89° incidence and both polarization modes.

Claims

1. A non-planar double resonant ring, characterized in that: The invention comprises a first metal wire (101) and a second metal wire (102); the first metal wire (101) and the second metal wire (102) are wound on different surfaces to form a double resonant ring; the first metal wire (101) and the second metal wire (102) are of equal length; and a first opening (201) and a second opening (202) are provided below the double resonant ring.

2. The eccentric double resonant ring according to claim 1, characterized in that: The material of the first metal wire (101) and the second metal wire (102) is one or more of silver, gold, aluminum, iron, tin and copper.

3. The eccentric double resonant ring according to claim 1, characterized in that: The cross-sectional shapes of the first metal wire (101) and the second metal wire (102) are one or more of circular, square, rectangular, triangular, and polygonal.

4. A two-dimensional array, characterized in that: The eccentric double resonant rings as claimed in claim 1 are used as structural units and arranged into an array.

5. The two-dimensional array according to claim 4, characterized in that: The array arrangement includes square, rectangular, centered cubic, rhombus, honeycomb hexagonal or any combination of the above array arrangements.

6. A three-dimensional array, characterized in that: The two-dimensional array as claimed in claim 4 is cascaded to form a three-dimensional array.

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