CN211265718U - VO-based2Super-surface dual-function device for realizing polarization conversion and wave absorption - Google Patents
VO-based2Super-surface dual-function device for realizing polarization conversion and wave absorption Download PDFInfo
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- CN211265718U CN211265718U CN201921831563.XU CN201921831563U CN211265718U CN 211265718 U CN211265718 U CN 211265718U CN 201921831563 U CN201921831563 U CN 201921831563U CN 211265718 U CN211265718 U CN 211265718U
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Abstract
The utility model discloses a based on VO2The super-surface dual-function device for realizing polarization conversion and wave absorption has a structure comprising a top-layer slotted circular metal patch, a second-layer dielectric plate and a third-layer slotted circular VO (vacuum) in sequence from top to bottom2A resonance unit, a dielectric plate on the fourth layer and a 4 'T' rotationally symmetrical VO on the fifth layer2A resonant unit, a medium plate on the sixth layer and a metal reflecting plate on the bottom layer. Using VO2The temperature control adjustability of (VO) is realized in a low temperature state, namely T is less than or equal to 68 DEG C2The resonant cell exhibits a dielectric behavior with a conductivity σ of 1 × 105S/m), the gold unit structure on the top layer realizes polarization conversion, and the working frequency band is 0.705-1.407 THz; at high temperature, namely T is more than or equal to 68 ℃ (VO)2The resonant cell is characterized by metal, and the conductivity sigma is 0.02S/m), VO2The resonance unit part plays a role in polarization cancellation, the whole structure achieves a wave absorbing function, the working frequency band of the resonance unit is 0.680-0.954 THz, and the resonance unit is a dual-function adjustable device. The utility model has the characteristics of design flexibility, functional strong, medium base plate are thin etc.
Description
Technical Field
The utility model relates to a multi-functional device that can regulate and control, especially one kind is based on VO2The super-surface dual-function device for realizing polarization conversion and wave absorption belongs to the technical field of terahertz wave band devices.
Background
Vanadium dioxide (VO)2) The film is a metal oxide with insulator-metal phase transition characteristic, and can be converted from an insulator state to a metal state under the action of light, heat or stress. VO accompanied by phase transition2Reversible mutations in the physical properties of the film can also occur. At present, based on VO2Metamaterials made by the thin film phase change principle have been applied to devices such as smart windows, microbolometers, and optical modulators. However, until now VO2The research on the application of the thin film to the tunable metamaterial wave absorber is very little.
A metamaterial is a periodically arranged artificially designed material that can be described by the effective permittivity and permeability of the material. The terahertz wave absorption has practical application value, and the wave absorption in the terahertz frequency band is realized shortly after the microwave band wave absorption is realized. The development direction of the metamaterial wave absorber is to overcome various problems, the metamaterial wave absorber is combined with equipment such as communication devices, motors and electric appliances, the metamaterial wave absorber which is miniaturized, multifunctional, low in cost and capable of being produced in a large area is designed, and diversified requirements in the aspect of practical application are met. The metamaterial wave absorber has important application in aspects such as a polarizing film, a detector, a stealth and a surface heat emitter, and particularly has application in the aspects of terahertz detection and solar energy collection, and double harvest is brought to economy and environment.
Disclosure of Invention
The utility model aims to solve the technical problem that the prior art is not enough to be overcome, and provide a VO-based2The super-surface dual-function device for realizing polarization conversion and wave absorption is realized by changing the shape of temperatureFormula (I) can change VO2Such that the function of the super-surface can be switched between a line-to-line polarization converter and a wave absorber.
The utility model discloses a solve above-mentioned technical problem and adopt following technical scheme:
according to the utility model provides a based on VO2The super-surface dual-function device for realizing polarization conversion and wave absorption comprises a slotted circular metal patch, a first layer of dielectric plate, a slotted circular VO2 resonance unit, a second layer of dielectric plate and a rotational symmetric VO which are sequentially stacked from top to bottom2The resonant unit, the third layer of dielectric plate and the metal reflecting plate;
the slotted circular metal patch is arranged on the top layer, a first slit is formed in the surface of the slotted circular metal patch along the circular lower right corner, a second slit and a third slit are symmetrically formed along the circular upper left corner, and the slotted circular VO2The resonance unit is formed by rotating the slotted circular patch at the top layer by 90 degrees, and the VO is rotationally symmetrical2The resonance unit is composed of a central square VO distributed in the center of the third dielectric plate2Square VO (vacuum oxide) with four corners of unit and third-layer dielectric plate2And (4) unit composition.
By changing the form of the temperature, VO can be changed2So that the function of the super surface can be switched between a linear-linear polarization converter and a wave absorber in a low-temperature state (VO) when T is less than or equal to 68 DEG C2The resonant unit has dielectric property, the conductivity sigma is 1 × 105S/m), the super-surface is a polarization converter, the working frequency band is 0.705-1.407 THz, the relative bandwidth is 66.477%, and the resonant unit is at a high temperature (VO) of more than or equal to 68 DEG C2The resonant unit is characterized by metal property, the conductivity sigma is 0.02S/m), the super-surface is a wave absorber, the absorption frequency band is 0.680-0.954 THz, and the relative bandwidth is 33.537%.
Furthermore, the slotted circular patch is formed by a circle with the radius r1 being 25um, wherein the circle is provided with a first slot at the center axis of the circle along 135 degrees from the lower right corner, and the circle is provided with a second slot and a third slot at the other two bisectors of the circle along-45 degrees from the upper left corner.
Further, the VO-based2For realizing polarization conversion and wave absorptionThe super-surface dual-function device is characterized in that the width of the first slit is w1 ═ 5um, and the distance of a diagonal line at the slit length exceeding 45 degrees of a circle is a ═ 15 um; the width w2 of the second and third slots is 3um, and the distance b of the diagonal line at the slot length exceeding 45 degrees is 10 um.
Further, the rotational symmetry VO2The resonance unit is composed of a central square VO2The cell and the square VO2 cell at the four corners, the central square VO2 cell is composed of 4T-shaped grooves which are rotationally symmetrical around the center and are arranged on the surface of a square with the side length of 5/9 × p (p is 60 um); the T-shaped grooves have an arm length of 5/9 × l1(l1 ═ 28um), a width of 5/9 × l2(l2 ═ 6um), and a line width of 5/9 × T3(T3 ═ 4 um); the square VO2 cells at the four corners were scaled by the central square VO2 cell scaling factor 9/20.
The first, second and third dielectric plates are made of Rogers RO4003C, dielectric constant 2 and loss tangent value 0.0027, the side length p of the dielectric substrate is 60um, the thickness t1 of the first and second dielectric plates is 1um, and the thickness t2 of the third dielectric plate is 28 um.
Further, the slotted circular metal patch material of top layer is gold, and its thickness is h ═ 0.2 um.
Further, the slotted circular VO2 resonant unit and the rotational symmetric VO2The materials of the resonant units are all VO2VO at low temperature, i.e. T is less than or equal to 68 DEG C2The electric conductivity sigma is 1 × 105S/m, and VO is at high temperature, i.e. T is more than or equal to 68 DEG C2Conductivity sigma is 0.02S/m, and the grooved circular VO2Resonant cell and rotationally symmetric VO2The thickness of each resonant unit is h-0.2 um.
The utility model adopts the above technical scheme to compare with prior art, have following technological effect:
(1) the utility model relates to a based on VO2The super-surface dual-function device for realizing polarization conversion and wave absorption innovatively utilizes the temperature adjustability of VO2 to change VO2So that the function of the super surface can be switched between a linear-linear polarization converter and a wave absorber at low temperatureIn the state, the super-surface is a polarization transformer; in a high-temperature state, the super surface is a wave absorber.
(2) The utility model is based on VO2The super-surface dual-function device for realizing polarization conversion and wave absorption has the advantages of flexible design, strong functionality, thin dielectric substrate and the like.
Drawings
Fig. 1 is a top view of the middle-top metal patch resonance unit of the present invention.
FIG. 2 shows the circular VO of the utility model2A top view of the resonant cell.
FIG. 3 shows the utility model of a medium rotational symmetry VO2A top view of the resonant cell.
Fig. 4 is a side view of the present invention.
Fig. 5 is a perspective view of the present invention.
Fig. 6 is a diagram (3 × 3) of a periodic array of the structural units according to the present invention.
Fig. 7 is a phase amplitude curve (uov mode) when T is less than or equal to 68 ℃.
FIG. 8 shows the reflection phase difference curve (uov mode) when the temperature of the present invention is low, i.e. T is less than or equal to 68 ℃.
FIG. 9 shows the reflection coefficient curve (xoy mode) of the present invention at a low temperature, i.e., T ≦ 68 ℃.
FIG. 10 shows the polarization conversion rate curve (xoy mode) of the present invention at low temperature, i.e., T ≦ 68 ℃.
FIG. 11 shows the absorption curve (xoy mode) of the present invention at a high temperature, i.e., T.gtoreq.68 ℃.
The reference signs explain: 1-slotted circular metal patch, 2-first dielectric slab, and 3-slotted circular VO2Resonant cell, 4-second layer dielectric slab, 5-rotational symmetric VO2The resonant unit, 6-third layer dielectric plate, 7-metal reflecting plate.
Detailed Description
The technical scheme of the present invention is further explained by combining the drawings and the specific embodiments as follows:
the utility model disclosesBased on VO2The super-surface dual-function device for realizing polarization conversion and wave absorption structurally comprises a slotted circular metal patch 1, a first dielectric plate 2 and a slotted circular VO (vacuum oxide semiconductor) of a third layer, which are sequentially arranged from top to bottom and arranged on a top layer2Rotationally symmetrical VO of resonance unit 3, second layer dielectric plate 4 and fifth layer2A resonant unit 5, a third layer of dielectric plate 6, a bottom layer of metal reflecting plate 7, a top layer of metal patch resonant unit, and a slotted circular VO2Resonance unit and rotational symmetry VO2Top views of the resonant cells are shown in fig. 1, 2, and 3, respectively. The super surface dual function device is shown in fig. 4 and 5 in a side view and a perspective view, respectively. Based on VO2The super-surface dual-function device for realizing polarization conversion and wave absorption is formed by periodically arranging unit structures, and a 3 × 3 array diagram of the super-surface dual-function device is shown in fig. 6.
The super-surface dual-function device uses VO2Temperature adjustability of, change VO2The shape and function of the wave absorber are such that the function of the super-surface can be switched between a linear-linear polarization converter and the wave absorber, and in a low-temperature state, the super-surface is a polarization converter; in a high-temperature state, the super surface is a wave absorber.
Based on VO2The method for producing the super-surface dual-function device for realizing polarization conversion and wave absorption is used when VO2VO at low temperature T not more than 68 DEG C2The resonant cells exhibit dielectric properties. At the moment, the linear polarization wave incident along the x axis of the electric field is vertically incident, and the linear-linear polarization conversion is generated by the action of the slotted circular metal patch 1 on the top layer. When VO is present2VO at high temperature, i.e. T is more than or equal to 68 DEG C2The resonant cells exhibit metallic properties. At this time, VO of the third layer2The resonance unit part plays the role of polarization cancellation, and the wave absorbing function is realized by a slotted circular VO2 Resonant cells 3 and 4 "T" rotationally symmetric VO2The resonant cell 5.
The dielectric layers of the second layer, the third layer and the sixth layer of the super-surface dual-function device are made of Rogers RO4003C, the dielectric constant is 2, and the loss tangent value is 0.0027.
Relevant parameters of the super-surface dual-function device are shown in the table 1.
| Parameter(s) | r1 | w1 | a | w2 |
| Value (um) | 25 | 5 | 15 | 3 |
| Parameter(s) | b | p | l1 | l2 |
| Value (um) | 10 | 60 | 28 | 6 |
| Parameter(s) | t3 | t1 | t2 | h |
| Value (um) | 4 | 1 | 28 | 0.2 |
TABLE 1
As shown in FIG. 7, it is the phase amplitude curve (uov mode) of the super-surface dual-function device in the low temperature state, i.e. T ≦ 68 ℃. To explain the working principle of the polarization converter more conveniently, we rotate the xoy coordinate system clockwise by 45 degrees, resulting in uov coordinate system (as shown in the lower left corner of fig. 1). Accordingly, we define the reflection coefficient as ruuAnd rvv。
Is the corresponding reflection phase. In addition, the phase difference can be determined by
To calculate. In order to obtain a cross-polarized wave, r must be satisfieduu≈rvv. In FIG. 7, the two amplitudes are substantially equal in the working frequency band of polarization conversion, i.e., 0.705-1.407 THz.
As shown in FIG. 8, it is the reflection phase difference curve (uov mode) of the super-surface dual-function device in the low temperature state, i.e. T ≦ 68 ℃. In order to achieve a completely orthogonal polarization rotation, a phase difference must be ensured
In fig. 8, within the working frequency band of polarization conversion, i.e., 0.705 to 1.407THz, the phase difference wanders up and down at ± 180 °, and the conversion from linear polarization waves to cross polarization waves is basically realized.
As shown in FIG. 9, it is the reflection coefficient curve (xoy mode) of the super-surface dual-function device in the low temperature state, i.e. T ≦ 68 ℃. As shown in FIG. 10, the super-surface dual function device is in a low temperature state, i.e. TPolarization conversion curve (xoy mode) at ≦ 68 ℃. The linear polarization reflection coefficient and the cross polarization reflection coefficient of the linearly polarized wave are respectively defined as rxxAnd ryxWherein the subscripts x and y represent the polarization direction of the electromagnetic wave. We define the polarization conversion ratio PCR ═ ryx 2/(rxx 2+ryx 2). There are three minimum points in fig. 9, at 0.743, 0.908, and 1.269THz, respectively. At these three resonance points, rxxIs close to 0, and ryxA maximum is reached which means that the incident wave in the x-direction is almost completely converted into a polarized wave in the y-direction. In FIG. 10, the PCR is greater than 0.9 in the working frequency band of 0.705-1.407 THz, and the conversion from linear polarized waves to cross polarized waves is basically realized.
As shown in FIG. 11, it is the absorption curve (xoy mode) of the super-surface dual-function device at high temperature, i.e. T.gtoreq.68 ℃. When VO is present2VO at high temperature, i.e. T is more than or equal to 68 DEG C2The resonant cells exhibit metallic properties. At this time, VO of the third layer2The resonance unit plays a role of polarization cancellation, and the whole structure realizes a wave absorbing function. The absorption formula a (ω) is 1-R (ω) -T (ω), where R (ω) represents the reflectance and T (ω) represents the transmittance. In fig. 11, the solid line and the dotted line are absorption curves in the TE mode and the TM mode, respectively, and it can be seen that the absorption curves in the TE mode and the TM mode are substantially the same, and in the absorbed operating band, that is, 0.680 to 0.954THz, the absorption rate is greater than 90%, and the relative bandwidth is 33.537%.
After the specific design, the utility model can change VO by changing the temperature2The shape and function of the super surface can be switched between a linear polarization converter and a wave absorber, and the super surface is the polarization converter in a low-temperature state, namely T is less than or equal to 68 ℃; when the temperature T is more than or equal to 68 ℃, the super surface is a wave absorber. The utility model has the characteristics of design flexibility, functional strong, medium base plate are thin etc.
The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are given by way of illustration only, and that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims. The scope of the invention is defined by the claims and their equivalents.
Claims (7)
1. VO-based2The super-surface dual-function device for realizing polarization conversion and wave absorption is characterized in that: comprises a slotted circular metal patch, a first layer of dielectric plate and a slotted circular VO which are sequentially stacked from top to bottom2Resonance unit, second dielectric plate and rotational symmetric VO2The resonant unit, the third layer of dielectric plate and the metal reflecting plate;
the slotted circular metal patch is arranged on the top layer, a first slit is formed in the surface of the slotted circular metal patch along the circular lower right corner, a second slit and a third slit are symmetrically formed along the circular upper left corner, and the slotted circular VO2The resonance unit is formed by rotating the slotted circular patch at the top layer by 90 degrees, and the VO is rotationally symmetrical2The resonance unit is composed of a central square VO distributed in the center of the third dielectric plate2Square VO (vacuum oxide) with four corners of unit and third-layer dielectric plate2And (4) unit composition.
2. VO-based according to claim 12The super-surface dual-function device for realizing polarization conversion and wave absorption is characterized in that: the slotted circular patch is composed of a radius r1The circle of 25um is provided with a first seam from the lower right corner along 135 degrees at the center axis of the circle, and is provided with a second seam and a third seam from the upper left corner along-45 degrees at the other two bisectors of the circle.
3. VO-based according to claim 22The super-surface dual-function device for realizing polarization conversion and wave absorption is characterized in that: the width of the first seam is w1The distance between the seam length and the diagonal line at 45 degrees of the circle is equal to 5um and equal to 15 um; the width w of the second and third seams23um, the distance b of the diagonal line at the position where the seam length exceeds 45 degrees of the circle is 10um。
4. VO-based according to claim 12The super-surface dual-function device for realizing polarization conversion and wave absorption is characterized in that: the rotational symmetry VO2The resonance unit is composed of a central square VO2Unit and square VO at four corners2Unit composition, center square VO2The unit is formed by opening 4T-shaped grooves which are rotationally symmetrical around the center on the surface of a square with the side length of 5/9 × p and p equal to 60 um; the arm length of the T-shaped groove is 5/9 × l1，l128um with a width of 5/9 × l2，l26um with an intermediate line width of 5/9 × t3，t34 um; square VO at four corners2The unit is composed of a central square VO2The cells are scaled by a scaling factor 9/20.
5. VO-based according to claim 12The super-surface dual-function device for realizing polarization conversion and wave absorption is characterized in that the first, second and third dielectric slabs are made of Rogers RO4003C, the dielectric constant is 2, the loss tangent value is 0.0027, the side length p of the dielectric substrate is 60um, and the thickness t of the first and second dielectric slabs is t11um, the thickness t of the third layer dielectric plate2＝28um。
6. VO-based according to claim 12The super-surface dual-function device for realizing polarization conversion and wave absorption is characterized in that: the slotted circular metal patch is made of gold, and the thickness of the slotted circular metal patch is h ═ 0.2 um.
7. VO-based according to claim 12The super-surface dual-function device for realizing polarization conversion and wave absorption is characterized in that the grooved circular VO2Resonant cell and rotationally symmetric VO2The materials of the resonant units are all VO2VO at low temperature, i.e. T is less than or equal to 68 DEG C2Conductivity σ 1 × 105S/m; VO at high temperature, T ≥ 68 ℃2Conductivity σ is 002S/m, the grooved circular VO2Resonant cell and rotationally symmetric VO2The thickness of each resonant unit is h-0.2 um.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112490678A (en) * | 2020-11-12 | 2021-03-12 | 云南师范大学 | VO-based2Broadband terahertz super-surface absorption unit and super-surface absorber |
| CN112864632A (en) * | 2020-12-31 | 2021-05-28 | 山西大学 | Asymmetric multifunctional metamaterial polarization converter |
| CN113131218A (en) * | 2021-03-29 | 2021-07-16 | 四川大学 | THz broadband switchable super surface for polarization conversion and wavefront regulation |
| CN113241531A (en) * | 2021-04-28 | 2021-08-10 | 大连理工大学 | Tunable array integrated broadband terahertz wave-absorbing resonator based on vanadium dioxide |
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2019
- 2019-10-29 CN CN201921831563.XU patent/CN211265718U/en active Active
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112490678A (en) * | 2020-11-12 | 2021-03-12 | 云南师范大学 | VO-based2Broadband terahertz super-surface absorption unit and super-surface absorber |
| CN112490678B (en) * | 2020-11-12 | 2022-11-01 | 云南师范大学 | VO-based2Broadband terahertz super-surface absorption unit and super-surface absorber |
| CN112864632A (en) * | 2020-12-31 | 2021-05-28 | 山西大学 | Asymmetric multifunctional metamaterial polarization converter |
| CN113131218A (en) * | 2021-03-29 | 2021-07-16 | 四川大学 | THz broadband switchable super surface for polarization conversion and wavefront regulation |
| CN113241531A (en) * | 2021-04-28 | 2021-08-10 | 大连理工大学 | Tunable array integrated broadband terahertz wave-absorbing resonator based on vanadium dioxide |
| CN113241531B (en) * | 2021-04-28 | 2022-04-12 | 大连理工大学 | Tunable array integrated broadband terahertz wave-absorbing resonator based on vanadium dioxide |
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