A fully polarized Fabry-Perot resonant material

Abstract

The present invention discloses a fully polarized Fabry-Perot resonant material, belonging to the field of artificial media technology. The material comprises at least four sub-wavelength unit structures. The sub-wavelength units include a first plate-shaped sub-unit parallel to the x-axis-y-axis plane; a second sub-unit, a cross-shaped cylinder composed of two mutually perpendicular surfaces parallel to the x-axis-z-axis plane and the y-axis-z-axis plane, respectively. The two first sub-units are mirror-symmetrically arranged at either end of the cross of the second sub-unit. The transformation optical device of the present invention can achieve complete transmission of TM-polarized waves and TE-polarized waves of a specified operating frequency at any incident angle. The Fabry-Perot resonant material of the present invention has a simple structure, thin thickness, and light weight, and is perfectly compatible with free space. It can be widely used in fields such as electromagnetic compatibility and electromagnetic interference resistance, such as aircraft, radar, and various other military fields.

Description

Technical Field

[0001] The present invention relates to the field of artificial medium technology, and in particular to a fully polarized Fabry-Perot resonant material realized based on an artificial electromagnetic medium construction method. Background Art

[0002] Transformation optics, which utilizes cleverly designed materials to greatly facilitate the manipulation of electromagnetic waves, has enabled scientists to design and implement a variety of novel optical devices, including cloaking devices, concentrators, lenses, curved waveguides, and retroreflectors.

[0003] Generally speaking, the constitutive parameters of ideal transformation optical devices (such as cloaking devices) are spatially non-uniform and often have extreme values, making their practical realization very difficult. Currently, in the field of transformation optics, uniform materials obtained through linear coordinate transformation are all materials that have undergone parameter simplification. Although designs based on parameter simplification can avoid parameter extremes and maintain the trajectory of light in the transformation optical device, they can produce unwanted reflections at the interface between the transformation optical device and the background medium.

[0004] Therefore, to ensure consistent propagation characteristics of a beam within a free-space transformation optical device regardless of its incident angle, a transparent material capable of full-angle matching is needed. Although some research teams have successfully developed a TM-polarized Fabry-Perot resonant material (e.g., prior art document 1: MMSadeghi, Sucheng Li, Lin Xu, Bo Hou*, and Huanyang Chen*, Transformation Optics with Fabry-Perot Resonances, Scientific Reports 5:8680, DOI:10.1038 / srep08680 (2015)), which can achieve a perfect transformation structure between two equal-sized planes in space, and this material allows TM-polarized electromagnetic waves to completely transmit without reflection at any incident angle, the polarization state of electromagnetic waves in practical applications is typically random and variable. Therefore, the development of fully polarized, all-angle Fabry-Perot resonant materials is crucial for realizing transformation optical devices such as fully polarized cloaking devices, concentrators, lenses, curved waveguides, and retroreflectors. Summary of the Invention

[0005] To address the problems mentioned in the background art, the present invention provides a fully polarized Fabry-Perot resonant material. By controlling the material's equivalent wave impedance to ensure it conforms strictly to the electromagnetic parameter form of the fully polarized Fabry-Perot resonant material, the material's equivalent wave impedance is now identical to that of free space, allowing electromagnetic waves of any polarization incident at any angle to fully transmit through the material without reflection.

[0006] The technical solution adopted in the present invention is as follows:

[0007] A fully polarized Fabry-Perot resonant material comprises at least four sub-wavelength unit structures; the sub-wavelength unit comprises a first sub-unit, the first sub-unit being plate-shaped and parallel to the x-axis-y-axis plane; and a second sub-unit, the second sub-unit being a cross-shaped column composed of two surfaces parallel to the x-axis-z-axis plane and the y-axis-z-axis plane, respectively, and perpendicular to each other, with two first sub-units being mirror-symmetrically arranged at opposite ends of the cross of the second sub-unit; the first sub-unit comprises a first dielectric plate, a first metal sub-wavelength open ring resonator, and a second metal sub-wavelength open ring resonator; the first metal sub-wavelength open ring resonator and the second metal sub-wavelength open ring resonator are respectively arranged on two side plate surfaces of the first dielectric plate, with the second metal sub-wavelength open ring resonator facing the second sub-unit; the second sub-unit comprises four branch dielectric plates, the four branch dielectric plates being connected in a cross-shaped manner; the branch dielectric plates comprise a second dielectric plate, a third dielectric plate, and a curved metal structure, with the second dielectric plate and the third dielectric plate clamping the curved metal structure.

[0008] In a preferred embodiment of the present invention, the first metal subwavelength open ring resonator is composed of two first open metal rings arranged symmetrically in the upper and lower parts, and the open end of each first open metal ring is facing the inner side of the first dielectric plate; the second metal subwavelength open ring resonator is composed of two second open metal rings arranged symmetrically in the left and right parts, and the open end of each second open metal ring is facing the inner side of the first dielectric plate.

[0009] In a preferred embodiment of the present invention, a gap is provided between the first open metal ring and the outer edge of the top surface of the first dielectric plate, and a gap is provided between the second open metal ring and the outer edge of the top surface of the first dielectric plate.

[0010] In a preferred embodiment of the present invention, the first open metal ring and the second open metal ring are open square rings.

[0011] In a preferred embodiment of the present invention, the main body of the bent metal structure in the branch dielectric plate is in a U shape. The bottom side part of the U shape is arranged on the side of the branch dielectric plate away from the center of the second sub-unit and extends to the edge of this side. The two side arms of the U shape in the bent metal structure are arranged in a coiled S shape.

[0012] In a preferred embodiment of the present invention, when the Fabry - Perot resonant material is composed of multiple sub - wavelength units, the orientations of the multiple sub - wavelength units are the same; the sub - wavelength units arranged along the x - axis direction or the y - axis direction are closely arranged, and the number of arrangements is a natural number greater than or equal to 1. The adjacent two sub - wavelength units arranged along the x - axis direction or the y - axis direction are butted through the second dielectric plate, the third dielectric plate and the bent metal structure; the sub - wavelength units arranged along the z - axis direction are arranged at equal intervals, and the number is an integer multiple of 4.

[0013] In a preferred embodiment of the present invention, the lengths of the first sub - unit and the second sub - unit in the x - axis direction are the same and less than 1 / 5 of the operating wavelength.

[0014] In a preferred embodiment of the present invention, the equivalent relative permittivity of the Fabry - Perot resonant material satisfies the form diag(A,A,∞) at the operating frequency, the equivalent permeability satisfies the form diag(B,B,∞) at the operating frequency, and the thickness of the Fabry - Perot resonant material 10 is an integer multiple of the length of the operating wavelength in the z - axis direction; in the forms diag(A,A,∞) and diag(B,B,∞), both A and B represent real values; taking the center of any one of the sub - wavelength units as the origin to construct a three - dimensional coordinate system, the fact that the equivalent relative permittivity satisfies the form diag(A,A,∞) means that the equivalent relative permittivity of the Fabry - Perot resonant material along the x - axis direction and along the y - axis direction is both A, and the equivalent relative permittivity along the z - axis direction is ∞; the fact that the equivalent permeability satisfies the form diag(B,B,∞) means that the equivalent permeability of the Fabry - Perot resonant material along the x - axis direction and along the y - axis direction is both B, and the equivalent permeability along the z - axis direction is ∞.

[0015] In a preferred embodiment of the present invention, the equivalent relative permittivity and equivalent magnetic permeability of the Fabry-Perot resonant material both satisfy the form of diag(C, D, ∞) at the operating frequency, and the thickness of the Fabry-Perot resonant material 10 is equal to an integer multiple of the length of the operating wavelength in the z-axis direction; in the form of diag(C, D, ∞), C and D both represent real values; a three-dimensional coordinate system is constructed with the center of any sub-wavelength unit as the origin, and the equivalent relative permittivity and equivalent magnetic permeability both satisfy the form of diag(C, D, ∞), indicating that the equivalent relative permittivity of the Fabry-Perot resonant material 10 along the x-axis direction is C, the equivalent relative permittivity along the y-axis direction is D, and the equivalent relative permittivity along the z-axis direction is ∞, the equivalent magnetic permeability of the Fabry-Perot resonant material 10 along the x-axis direction is C, the equivalent magnetic permeability along the y-axis direction is D, and the equivalent magnetic permeability along the z-axis direction is ∞.

[0016] In a preferred embodiment of the present invention, the first dielectric plate, the second dielectric plate and the third dielectric plate are made of F4B dielectric; the first metal subwavelength open ring resonator, the second metal subwavelength open ring resonator and the curved metal structure are made of metal copper.

[0017] This invention constructs an ideal transformation optical device in free space, capable of achieving complete transmission of TM-polarized waves and TE-polarized waves of a specified operating frequency at any angle of incidence. The Fabry-Perot resonant material of this invention boasts a simple structure, thin thickness, and lightweight, perfectly matching the free-space environment. It can be widely used in fields such as electromagnetic compatibility and electromagnetic interference mitigation, including aircraft, radar, and other military applications.

[0018] In order to make the above features and advantages of the present invention more clearly understood, embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG1( a ) is a perspective view of the structure of a sub-wavelength unit in a Fabry-Perot resonant material of the present invention.

[0020] FIG1( b ) is an exploded perspective view of the sub-unit structure of the sub-wavelength unit of the present invention.

[0021] FIG2( a ) is a left side view of the first subunit in the sub-wavelength unit of the present invention.

[0022] FIG2( b ) is a right side view of the first subunit in the sub-wavelength unit of the present invention.

[0023] FIG2( c ) is a top view of the first subunit in the sub-wavelength unit of the present invention.

[0024] FIG3( a ) is a top view of the second subunit in the sub-wavelength unit of the present invention.

[0025] FIG3( b ) is a side view of the second subunit in the sub-wavelength unit of the present invention.

[0026] FIG3( c ) is a front view of the second subunit in the sub-wavelength unit of the present invention.

[0027] FIG3( d ) is a perspective view of the second subunit in the sub-wavelength unit of the present invention.

[0028] Figure 4 Schematic diagram of multiple sub-wavelength units arranged to form a Fabry-Perot resonant material.

[0029] FIG5( a ) is a phase spectrum simulation diagram of the Fabry-Perot resonant material in the example when TE polarized waves are incident at multiple angles.

[0030] FIG5( b ) is a simulation diagram of the amplitude spectrum of the Fabry-Perot resonant material in the example when TE polarized waves are incident at multiple angles.

[0031] FIG6( a ) is a phase spectrum simulation diagram of the Fabry-Perot resonant material in the example when TM polarized waves are incident at multiple angles.

[0032] FIG6( b ) is a simulation diagram of the amplitude spectrum of the Fabry-Perot resonant material in the example when TM polarized waves are incident at multiple angles.

[0033] Description of Reference Numerals

[0034] 10Fabry-Perot resonant materials

[0035] 100th wavelength unit

[0036] 110 first subunit

[0037] 111 first dielectric plate

[0038] 112 The first metal subwavelength open ring resonator

[0039] 1121 First Open Metal Ring

[0040] 113 Second Metal Subwavelength Open Ring Resonator

[0041] 1131 Second open metal ring

[0042] 120 Second subunit

[0043] 121 branch medium board

[0044] 122 second dielectric plate

[0045] 123 third medium board

[0046] 124 curved metal structures

[0047] 200 intervals DETAILED DESCRIPTION

[0048] To make the purpose and technical solutions of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] Figure 1(a) is a perspective view of the structure of a subwavelength unit in a Fabry-Perot resonant material according to the present invention, and Figure 1(b) is a disassembled perspective view of the sub-unit structure in a subwavelength unit according to the present invention. As shown in Figures 1(a) and 1(b), the Fabry-Perot resonant material 10 according to the present invention includes at least four subwavelength units 100, each of which includes two first sub-units 110 and a second sub-unit 120. The second sub-unit 120 is a cross-shaped column, and the two first sub-units 110 are plate-shaped and are mirror-symmetrically arranged at the two ends of the cross of the second sub-unit 120. As shown in the coordinate system in Figure 1, the two faces of the cross-shaped column constituting the second sub-unit 120 are perpendicular to each other and parallel to the x-axis-z-axis plane and the y-axis-z-axis plane, respectively. The second sub-unit 120 forms two cross-shaped end faces on the x-axis-y-axis plane. The two first subunits 110 are parallel to the x-y axis plane and are respectively located on the two cross-shaped end faces on the left and right sides of the second subunit 120. After being combined with the second subunit 120, the overall structure is roughly I-shaped.

[0050] The first subunit 110 includes a first dielectric plate 111, a first metal subwavelength split ring resonator 112, and a second metal subwavelength split ring resonator 113. The first metal subwavelength split ring resonator 112 and the second metal subwavelength split ring resonator 113 are respectively disposed on two side surfaces of the first dielectric plate 111, with the second metal subwavelength split ring resonator 113 facing the second subunit 120.

[0051] The second subunit 120 includes four branching dielectric plates 121, which are connected in a cross-shaped pattern to form the second subunit 120. The branching dielectric plates 121 include a second dielectric plate 122, a third dielectric plate 123, and a curved metal structure 124. The second dielectric plates 122 and the third dielectric plates 123 sandwich the curved metal structure 124, and the three dielectric plates are stacked to form a single branching dielectric plate 121.

[0052] FIG2(a), FIG2(b) and FIG2(c) are respectively a left view, a right view and a top view of the first subunit in the sub-wavelength unit of the present invention. Figure 2(a) to Figure 2(c) Corresponding to the first sub-unit 110 on the left side in Fig. 1(a), the first sub-unit 110 on the right side is mirror-symmetrical to the structure on the left side.

[0053] As shown in the figure, the first metal sub-wavelength open-loop resonator 112 is disposed on one side surface of the first dielectric plate 111. The first metal sub-wavelength open-loop resonator 112 is composed of two first open metal rings 1121 arranged symmetrically up and down, and there is a gap between the first open metal ring 1121 and the outer edge of the top surface of the first dielectric plate 111. The main body of the first open metal ring 1121 is an open square ring, and the open end of each first open metal ring 1121 faces the inner side of the first dielectric plate 111.

[0054] The second metal sub-wavelength open-loop resonator 113 is disposed on the other side surface of the first dielectric plate 111. The second metal sub-wavelength open-loop resonator 113 is composed of two second open metal rings 1131 arranged symmetrically left and right, and there is a gap between the second open metal ring 1131 and the outer edge of the top surface of the first dielectric plate 111. The main body of the second open metal ring 1131 is an open square ring, and the open end of each second open metal ring 1131 faces the inner side of the first dielectric plate 111.

[0055] Figs. 3(a), 3(b), 3(c), and 3(d) are respectively the top view, side view, front view, and three-dimensional view of the second sub-unit in the sub-wavelength unit of the present invention. As shown in the figure, the second sub-unit 120 is composed of four branch dielectric plates 121 cross-connected in a cross shape. The main body of the curved metal structure 124 in the branch dielectric plate 121 is in a U shape, the bottom side of the U shape is arranged on the side of the branch dielectric plate 121 away from the center of the second sub-unit 120 and extends to the edge of this side, and the two side arms of the U shape in the curved metal structure 124 are arranged in a coiled S shape.

[0056] Figure 4 Schematic diagram of a Fabry-Perot resonant material composed of multiple sub-wavelength units arranged. As Figure 4 shown, the minimum structure of the Fabry-Perot resonant material 10 is composed of four sub-wavelength units 100. The four sub-wavelength units 100 are arranged in the same orientation and are equally spaced along the z-axis direction. It is defined that the z-axis direction is the direction of the intersection line of the planes where the four branch dielectric plates 121 in a single sub-wavelength unit 100 are located, the y-axis direction is the direction parallel to the two side arms of the U shape of the curved metal structure 124, and the x-axis direction is the direction perpendicular to the z-axis and perpendicular to the y-axis.

[0057] When a Fabry-Perot resonant material 10 is composed of a plurality of sub-wavelength units 100, the sub-wavelength units 100 arranged along the x-axis or the y-axis are closely arranged, and the number of arranged sub-wavelength units 100 is a natural number greater than or equal to 1. Two adjacent sub-wavelength units 100 arranged along the x-axis or the y-axis are butted together via the second dielectric plate 122, the third dielectric plate 123, and the curved metal structure 124. The sub-wavelength units 100 arranged along the z-axis are equidistantly arranged, and the number is an integer multiple of 4. A gap 200 is provided between two adjacent sub-wavelength units 100 arranged along the z-axis, and the gap 200 is preferably 0.5 mm.

[0058] When TM polarized waves or TE polarized waves are used as working waves, the relationship between the working frequency and the working wavelength of the working wave satisfies λ=c / f, where λ is the working wavelength, c is the speed of light in vacuum, and f is the working frequency.

[0059] Preferably, the first dielectric plate 111 in the sub-wavelength unit 100 is a square plate, and the side length of the first dielectric plate 111 is less than 1 / 5 of the operating wavelength. The second dielectric plate 122 and the third dielectric plate 123 have the same length and width, and the width of the second dielectric plate 122 and the third dielectric plate 123 on the side facing the first sub-unit 110 is equivalent to half the side length of the first dielectric plate 111. That is, the first sub-unit 110 and the second sub-unit 120 have the same length in the x-axis direction and are less than 1 / 5 of the operating wavelength.

[0060] Since the overall length, width and height of a single sub-wavelength unit 100 in the Fabry-Perot resonant material 10 are much smaller than the operating wavelength, the Fabry-Perot resonant material 10 can be regarded as a homogeneous medium. The equivalent relative dielectric constant and equivalent magnetic permeability of the Fabry-Perot resonant material 10 can be inverted through the reflection coefficient and transmission coefficient of the Fabry-Perot resonant material 10.

[0061] By adjusting the physical dimensions of the Fabry-Perot resonant material 10, the equivalent relative permittivity of the Fabry-Perot resonant material 10 satisfies the form of diag(A, A, ∞) at the operating frequency, and the equivalent magnetic permeability satisfies the form of diag(B, B, ∞) at the operating frequency, or both the equivalent relative permittivity and the equivalent magnetic permeability satisfy the form of diag(C, D, ∞), and the thickness of the Fabry-Perot resonant material 10 in the z-axis direction is equal to an integer multiple of the length of the operating wavelength in the z-axis direction, so that TM-polarized and TE-polarized electromagnetic waves incident from any angle can completely pass through the Fabry-Perot resonant material without reflection.

[0062] In the above-mentioned diag(A,A,∞) form, diag(B,B,∞) form, and diag(C,D,∞) form, A, B, C, and D all represent real values; a three-dimensional coordinate system is constructed with the center of any sub-wavelength unit 100 as the origin, and the equivalent relative dielectric constant satisfies the diag(A,A,∞) form, indicating that the equivalent relative dielectric constant of the Fabry-Perot resonant material 10 along the x-axis direction and the equivalent relative dielectric constant along the y-axis direction are both A, and the equivalent relative dielectric constant along the z-axis direction is ∞; the equivalent magnetic permeability satisfies the diag(B,B,∞) form, indicating that the equivalent magnetic permeability of the Fabry-Perot resonant material 10 along the x-axis direction and the equivalent magnetic permeability along the y-axis direction are both B, and the equivalent magnetic permeability along the z-axis direction is ∞. The equivalent relative permittivity and the equivalent permeability both satisfy the form of diag(C, D, ∞), indicating that the equivalent relative permittivity of the Fabry-Perot resonant material 10 along the x-axis is C, the equivalent relative permittivity along the y-axis is D, and the equivalent relative permittivity along the z-axis is ∞; the equivalent permeability of the Fabry-Perot resonant material 10 along the x-axis is C, the equivalent permeability along the y-axis is D, and the equivalent permeability along the z-axis is ∞.

[0063] Preferably, the first dielectric plate 111, the second dielectric plate 122 and the third dielectric plate 123 are all made of F4B dielectric. The first metal subwavelength open ring resonator 112, the second metal subwavelength open ring resonator 113 and the curved metal structure 124 are preferably made of copper.

[0064] The working principle of the Fabry-Perot resonant material of the present invention is as follows.

[0065] Since the thickness of the sub-wavelength unit 100 in the Fabry-Perot resonant material 10 is much smaller than the working wavelength, the Fabry-Perot resonant material 10 can be equivalent to a uniform medium, and its equivalent relative dielectric constant can be expressed as Its equivalent relative permeability can be expressed as

[0066] In addition, in order to satisfy the Fabry-Perot resonance effect, the total thickness L of the Fabry-Perot resonance material 10 in the z-axis direction should be an integer multiple of the operating wavelength in the z-axis direction, that is, L = m2π / k z (m=1,2,3·····), where k z represents the component of the wave vector in the Fabry-Perot resonant material 10 in the z-axis direction.

[0067] The equivalent homogeneous medium is a dispersive medium, meaning that both the relative permittivity and relative permeability vary with frequency. Since the magnetic permeability μ of most natural media is 1, the first and second metal subwavelength split ring resonators 112 and 113 are constructed perpendicular to each other in the x-axis-y-axis plane. By manually controlling the physical dimensions of the first and second metal subwavelength split ring resonators 112 and 113, an equivalent permeability that conforms to the Lorentz dispersion model can be obtained within a certain frequency band, which is manually controllable, resulting in B = 1.85. The first and second metal subwavelength split ring resonators 112 and 113 are constructed perpendicular to each other in the x-axis-y-axis plane to ensure that TM-polarized electromagnetic waves and TE-polarized electromagnetic waves have the same permeability when incident at any angle. The curved metal structure 124 arranged along the z-axis direction is composed of a curved metal transmission line. The curved metal transmission line is provided to introduce equivalent capacitance and inductance, thereby obtaining an equivalent dielectric constant dispersion that can be artificially controlled. By adjusting the physical dimensions of the curved metal structure 124, the Fabry-Perot resonant material can achieve A = 4.48 at a certain frequency. By adjusting the structural dimensions of the first metal subwavelength open ring resonator 112, the second metal subwavelength open ring resonator 113 and the curved metal structure 124, they are caused to resonate so that the equivalent relative dielectric constant ε in the z-axis direction is z and equivalent magnetic permeability μ z Satisfy ε z =μ z =∞. The above design makes the material satisfy the Fabry-Perot resonance effect, so that TM polarized waves and TM polarized waves incident from any angle will completely pass through the material, with a reflection coefficient of zero and a refractive index of

[0068] by Figure 4 Taking the Fabry-Perot resonant material 10 composed of four sub-wavelength units 100 as an example, the length of each sub-wavelength unit 100 in the y-, x-, and z-axes is 5 mm. The four sub-wavelength units 100 are spaced apart along the z-axis to achieve a fully angularly perfectly matched Fabry-Perot resonant material 10 in free space. In this embodiment, the first dielectric plate 111, the second dielectric plate 122, and the third dielectric plate 123 are all F4B dielectrics with a thickness of 0.25 mm. The copper used in the first metal sub-wavelength split ring resonator 112, the second metal sub-wavelength split ring resonator 113, and the curved metal structure 124 is all 0.018 mm thick.

[0069] like Figure 2(a) to Figure 3(c)As shown, the dimensions of each part of the sub-wavelength unit 100 are as follows: a = 5 mm, a1 = 0.875 mm, a2 = 0.2 mm, a3 = 0.3 mm, a4 = 0.875 mm, w1 = 3.25 mm, w2 = 1.475 mm, w3 = 0.2 mm, t1 = 0.268 mm, t2 = 0.018 mm, t3 = 0.52 mm, p = 4.5 mm, l1 = 2.08 mm, l2 = 0.075 mm, l3 = 0.15 mm, l4 = 0.15 mm, l5 = 0.45 mm, l6 = 0.966 mm, l7 = 0.15 mm, l8 = 0.04 mm. Based on the numerical values ​​of the above example, a simulation of the Fabry-Perot resonant material 10 was performed.

[0070] Figure 5(a) shows a simulated phase spectrum of the Fabry-Perot resonant material in the example when subjected to TE-polarized waves incident at multiple angles. Figure 5(b) shows a simulated amplitude spectrum of the Fabry-Perot resonant material in the example when subjected to TE-polarized waves incident at multiple angles. As shown in Figures 5(a) and 5(b), the simulation results for TE-polarized waves show that at 9.48 GHz, when the phase of the incident TE-polarized electromagnetic wave increases from 0 degrees to 80 degrees, the reflection coefficient is <-20 dB, and the phase is 0.

[0071] Figure 6(a) shows a simulated phase spectrum of the Fabry-Perot resonant material in the example when subjected to TM-polarized waves at multiple incident angles. Figure 6(b) shows a simulated amplitude spectrum of the Fabry-Perot resonant material in the example when subjected to TM-polarized waves at multiple incident angles. As shown in Figures 6(a) and 6(b), the simulation results for TM-polarized waves show that at 9.48 GHz, when the phase of the incident TM-polarized electromagnetic wave increases from 0 to 80 degrees, the reflection coefficient is <-20 dB, and the phase is 0.

[0072] The Fabry-Perot resonant material 10 in the example has good matching characteristics with free space at a frequency of 9.48 GHz. If the present invention is to work at other frequencies, it is necessary to appropriately adjust the sizes of the first metal subwavelength open ring resonator 112, the second metal subwavelength open ring resonator 113 and the curved metal structure 124 according to the working wavelength, so that their equivalent relative dielectric constant satisfies the form of diag(A,A,∞) and the equivalent magnetic permeability satisfies the form of diag(B,B,∞) at the set working frequency, or both the equivalent relative dielectric constant and the equivalent magnetic permeability satisfy the form of diag(C,D,∞).

[0073] In summary, the present invention constructs an ideal transformation optical device in free space, capable of achieving complete transmission of TM-polarized waves and TE-polarized waves of a specified operating frequency at any angle of incidence. The present Fabry-Perot resonant material exhibits a simple structure, thin thickness, and lightweight, perfectly matching the free-space environment. It can be widely used in fields such as electromagnetic compatibility and electromagnetic interference mitigation, including aircraft, radar, and various other military applications.

[0074] The above examples do not limit the present invention in any form. Any technician familiar with the present profession can use the technical content disclosed above to change or modify it into equivalent examples with equivalent changes. However, any simple modifications, equivalent changes and modifications made to the above examples based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A fully polarized Fabry-Perot resonant material, characterized in that: including at least four sub-wavelength unit structures; the sub-wavelength unit includes, a first sub-unit, the first sub-unit is plate-shaped and parallel to the x-axis - y-axis plane; and, a second sub-unit, the second sub-unit is a cross-shaped cylinder composed of two faces perpendicular to each other and parallel to the x-axis - z-axis plane and the y-axis - z-axis plane respectively. Each sub-wavelength unit includes two first sub-units and a second sub-unit. The two first sub-units are respectively arranged symmetrically by mirror image at both ends of the cross of the second sub-unit; the first sub-unit includes a first dielectric plate, a first metal sub-wavelength open-loop resonator, and a second metal sub-wavelength open-loop resonator; the first metal sub-wavelength open-loop resonator and the second metal sub-wavelength open-loop resonator are respectively arranged on both side surfaces of the first dielectric plate, and the second metal sub-wavelength open-loop resonator faces the second sub-unit; the second sub-unit includes four branch dielectric plates, and the four branch dielectric plates are cross-connected; the branch dielectric plate includes a second dielectric plate, a third dielectric plate, and a bent metal structure. The second dielectric plate and the third dielectric plate sandwich the bent metal structure, and the three are stacked to form one branch dielectric plate; the sub-wavelength units arranged along the x-axis direction or the y-axis direction are closely arranged, and the number of arrangements is a natural number greater than or equal to 1. The adjacent two sub-wavelength units arranged along the x-axis direction or the y-axis direction are docked through the second dielectric plate, the third dielectric plate, and the bent metal structure; the sub-wavelength units arranged along the z-axis direction are arranged at equal intervals, and the number is an integer multiple of 4.

2. The all-polarization Fabry-Perot resonant material according to claim 1, wherein, the first metal sub-wavelength open-loop resonator is composed of two first open metal rings arranged symmetrically up and down, and the open ends of each first open metal ring face the inside of the first dielectric plate; the second metal sub-wavelength open-loop resonator is composed of two second open metal rings arranged symmetrically left and right, and the open ends of each second open metal ring face the inside of the first dielectric plate.

3. The fully polarized Fabry-Perot resonant material according to claim 2, wherein: There is a gap between the first open metal ring and the outer edge of the top surface of the first dielectric plate, and there is a gap between the second open metal ring and the outer edge of the top surface of the first dielectric plate.

4. The fully polarized Fabry-Perot resonant material according to claim 2, wherein: The first open metal ring and the second open metal ring are open square rings.

5. The fully polarized Fabry-Perot resonant material according to claim 1, wherein: The main body of the bent metal structure in the branch dielectric plate is in a U shape, and the bottom part of the U shape is arranged on the side of the branch dielectric plate away from the center of the second sub-unit and extends to the edge of this side. The two side arms of the U shape in the bent metal structure are arranged in an S-shaped coil.

6. The fully polarized Fabry-Perot resonant material according to claim 1, wherein: When the Fabry-Perot resonant material is composed of multiple sub-wavelength units, the arrangements of the multiple sub-wavelength units have the same orientation.

7. The fully polarized Fabry-Perot resonant material according to claim 1, wherein: The first sub-unit and the second sub-unit have the same length in the x-axis direction and are less than 1 / 5 of the working wavelength.

8. The fully polarized Fabry-Perot resonant material according to claim 1, wherein: The equivalent relative dielectric constant of the Fabry-Perot resonant material satisfies the form of diag(A, A, ∞) at the operating frequency, and the equivalent magnetic permeability satisfies the form of diag(B, B, ∞) at the operating frequency, and the thickness of the Fabry-Perot resonant material (10) is equal to an integer multiple of the length of the operating wavelength in the z-axis direction; in the form of diag(A, A, ∞) and the form of diag(B, B, ∞), A and B both represent real values; a three-dimensional coordinate system is constructed with the center of any one of the sub-wavelength units as the origin, and the equivalent relative dielectric constant satisfies the form of diag(A, A, ∞), indicating that the equivalent relative dielectric constant of the Fabry-Perot resonant material along the x-axis direction and the equivalent relative dielectric constant along the y-axis direction are both A, and the equivalent relative dielectric constant along the z-axis direction is ∞; the equivalent magnetic permeability satisfies the form of diag(B, B, The form of ∞) indicates that the equivalent magnetic permeability of the Fabry-Perot resonant material along the x-axis and the equivalent magnetic permeability along the y-axis are both B, and the equivalent magnetic permeability along the z-axis is ∞.

9. The fully polarized Fabry-Perot resonant material according to claim 1, wherein: The equivalent relative dielectric constant and equivalent magnetic permeability of the Fabry-Perot resonant material satisfy the form of diag(C, D, ∞) at the operating frequency, and the thickness of the Fabry-Perot resonant material (10) is equal to an integer multiple of the length of the operating wavelength in the z-axis direction; in the form of diag(C, D, ∞), C and D both represent real values; a three-dimensional coordinate system is constructed with the center of any sub-wavelength unit as the origin, and the equivalent relative dielectric constant and equivalent magnetic permeability both satisfy the form of diag(C, D, ∞), indicating that the equivalent relative dielectric constant of the Fabry-Perot resonant material (10) along the x-axis direction is C, the equivalent relative dielectric constant along the y-axis direction is D, and the equivalent relative dielectric constant along the z-axis direction is ∞, the equivalent magnetic permeability of the Fabry-Perot resonant material (10) along the x-axis direction is C, the equivalent magnetic permeability along the y-axis direction is D, and the equivalent magnetic permeability along the z-axis direction is ∞.

10. The fully polarized Fabry-Perot resonant material according to claim 1, wherein: The first dielectric plate, the second dielectric plate, and the third dielectric plate are made of F4B dielectric; the first metal subwavelength open ring resonator, the second metal subwavelength open ring resonator, and the curved metal structure are made of copper.

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