CN113690624A - Vortex optical spatial modulator based on geometric phase super-surface - Google Patents
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- H01Q15/0006—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices
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- H01Q15/0006—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices
- H01Q15/0013—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices said selective devices working as frequency-selective reflecting surfaces, e.g. FSS, dichroic plates, surfaces being partly transmissive and reflective
- H01Q15/002—Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices said selective devices working as frequency-selective reflecting surfaces, e.g. FSS, dichroic plates, surfaces being partly transmissive and reflective said selective devices being reconfigurable or tunable, e.g. using switches or diodes
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- H01Q3/26—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture
- H01Q3/30—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array
- H01Q3/34—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array by electrical means
- H01Q3/36—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array by electrical means with variable phase-shifters
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Abstract
本发明公开一种基于几何相位超表面的涡旋光空间调制器，包括呈阵列排布的M×M个超表面像素单元，每个超表面像素单元可独立地完成涡旋子光束的生成与关闭，进而实现阵列化的螺旋相位调控或涡旋子光束阵列的空间调控。器件工作在反射模式，每一个子单元涡旋光超表面发生器采用金属‑介质‑金属三层架构，即顶层为实现几何相位调控的纳米天线，中间层为相变介质与SiO2匹配层，底层为金属层；通过基于TFT驱动阵列设计的电控激励加载，当相变介质层为非晶态时，入射电磁波以理想的阻抗匹配工作在特定的谐振频率，交叉极化效率大，涡旋光产生效率大；从非晶态切换为晶态时，谐振偏移原来的工作波段，能量转化率小，螺旋相位关闭。
The invention discloses a vortex light spatial modulator based on a geometric phase metasurface, comprising M×M metasurface pixel units arranged in an array, and each metasurface pixel unit can independently complete the generation and closing of the vortex sub-beam, Furthermore, the arrayed helical phase modulation or the spatial modulation of the vortex beamlet array can be realized. The device works in reflection mode, and each subunit vortex optical metasurface generator adopts a metal-dielectric-metal three-layer structure, that is, the top layer is a nano-antenna for geometric phase control, the middle layer is a phase change medium and SiO 2 matching layer, and the bottom layer is a matching layer of phase change medium and SiO 2 . It is a metal layer; through the electronically controlled excitation loading based on the design of the TFT drive array, when the phase change dielectric layer is amorphous, the incident electromagnetic wave works at a specific resonance frequency with ideal impedance matching, the cross-polarization efficiency is high, and the vortex light is generated. High efficiency; when switching from an amorphous state to a crystalline state, the resonance shifts from the original working band, the energy conversion rate is small, and the helical phase is closed.
Description
Technical Field
The invention belongs to the field of phase regulation of electromagnetic waves, and particularly relates to a vortex optical spatial modulator based on a geometric phase super-surface.
Background
The super surface is composed of sub-wavelength periodic units, and the characteristics which are not possessed by natural materials, such as negative refractive index, negative magnetic permeability and the like, can be realized by utilizing resonance among the units, so that the super surface has numerous applications in optical bands of visible light, infrared, terahertz and the like, such as superlenses, holography, abnormal deflection, vortex rotation and the like. The phase-modulated super surface can be divided into a transmission phase type super surface, a geometric phase type super surface and a circuit type super surface. Due to the characteristics of the super surface, the super surface device can only work in a specific narrow band, and is difficult in wiring and manufacturing process. The geometric phase super surface utilizes anisotropic 'elements' with the same size to rotate a certain angle to obtain a change of a space phase, so that electromagnetic waves are regulated and controlled, and the machining and manufacturing difficulty of the super surface is reduced due to the characteristic of the geometric phase.
Once the material and structure parameters of a general super-surface device are determined, the working frequency, bandwidth and other properties of the super-surface device are determined, in order to realize the popularization and wide application of the super-surface device, dynamic active regulation is added into the super-surface device to become a great hot point, and the current mainstream method is to add a phase-change medium into the middle of the super-surface. The principle is mainly to change the dielectric constant of the super surface and realize good frequency shift effect. The phase change materials commonly used in the sub-wavelength structure design include GST, vanadium oxide and memory alloy, wherein the GST material has non-volatility and reversibility, good thermal stability and high switching speed, can generally realize the change of crystalline state and amorphous state through electric excitation, thermal excitation, optical excitation and the like, and is widely applied to the phase change materials.
The spatial light modulator is used as a key device for optical information processing, and has great regulation and control functions on the amplitude, the phase, the polarization state and the like of light. The spiral phase modulation in the phase control is a new research direction, vortex light has the characteristics of spiral phase, orbital angular momentum and the like, the edge enhancement effect can be obtained by combining radial Hilbert transformation in object imaging, the imaging quality of the object can be improved by utilizing the spiral phase and the annular light field of vortex optical rotation, the diffraction limit is broken through, and the application potential in the fields of space division multiplexing optical communication, stimulated radiation loss imaging, infrared imaging, sensing and the like is very great. However, at present, the transmissive optical modulator has the disadvantages of low light transmittance, large light energy loss, low light intensity contrast ratio and the like.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a vortex optical spatial modulator based on a geometric phase super surface, which can reduce the volume of the spatial light modulator, reduce the optical energy loss and enhance the image quality by spirally reconstructing a super surface pixel unit, wherein the spatial light modulator is of a reflection type.
In order to achieve the above purpose, the invention provides a vortex optical spatial modulator based on a geometric phase super-surface, and the device is composed of M × M array sub-super-surface pixel units, and each super-surface pixel unit can independently complete the generation and closing of vortex sub-beams, thereby achieving arrayed spiral phase regulation or spatial regulation of vortex sub-beam arrays. The single super-surface pixel unit is arrayed, and independent pixel point control can be realized.
Furthermore, each super-surface pixel unit can be regarded as a subunit vortex optical super-surface generator consisting of N multiplied by N sub-wavelength antennas which are arranged in an array, each subunit vortex optical super-surface generator can independently realize dynamic reconfiguration of a sub-beam spiral phase, each subunit vortex optical super-surface generator comprises a sub-wavelength antenna layer, a phase change dielectric layer, an insulating dielectric layer and a metal reflecting layer which are arranged from top to bottom, and dynamic reconfiguration of the sub-beam spiral phase is independently realized.
Furthermore, the subunit vortex optical super-surface generator can control state switching through electric excitation and optical excitation, and the like, realizes the switching effect of an on state and an off state in a middle infrared band, and can realize independent pixel point control through arraying of single super-surface pixel units.
Furthermore, the subunit vortex optical super-surface generator, the sub-wavelength antenna layer is made of noble metal material, and the phase change medium layer is made of Ge2Sb2Te5The medium insulating medium layer is made of SiO2The metal reflecting layer is made of noble metal.
Furthermore, the working wavelength is 3-4 μm of the intermediate infrared band, the thickness of the phase change medium layer is 0.03-0.07 μm, and the length and width of the phase change medium layer are consistent with those of the intermediate medium layer and the metal reflecting layer.
Further, the geometric phase is discrete, and the period of the sub-wavelength antenna layer is far less than the wavelength as possible, so that the continuous distribution of the generated vortex phase can be ensured.
Furthermore, after the super-surface pixel units are arrayed, each pixel is controlled through independent addressing of electric excitation loading, and electric addressing and switch control of the spatial light modulator are achieved.
Furthermore, the electric addressing control of the super-surface pixel unit adopts a driving array design based on a TFT field effect transistor, the grid electrode, the source electrode and the drain electrode of the TFT field effect transistor are respectively connected with the row electrode, the column electrode and the super-surface pixel unit, and the transition between the crystalline state and the amorphous state is realized by electrically exciting a GST phase change medium.
Compared with the prior art, the invention has at least the following beneficial effects:
the vortex reconfigurable spatial light modulator based on the geometric phase is characterized in that the uppermost layer of the super-surface pixel unit is a sub-wavelength antenna array, vortex light is generated by utilizing the characteristic of the geometric phase, spiral phase modulation is realized, the super-surface pixel unit can be analogized to a filter based on radial Hilbert transform, imaging has extremely high contrast, clearer image edge information can be obtained, and image quality is enhanced; secondly, a phase change medium layer is arranged, and the vortex based on the phase change medium layer canAnd the reconfiguration optimizes the switching performance of the spatial light modulator, and when the thickness of the subunit vortex optical super-surface generator is changed, the working wavelength is changed. The invention can reflect the existence of vortex through the existence of geometric phase, and the subunit vortex optical super-surface generator and the material are Ge2Sb2Te5The phase change medium layer can realize good switching effect between the wavelengths of 3-4 mu m, and when the phase change medium layer is made of Ge2Sb2Te5(GST) is in amorphous state and is in switch open state 1, and has high geometric phase occupation ratio, and Ge is used as material of phase change medium layer2Sb2Te5In the crystalline state, (GST) has little geometric phase, and is in the off state "0" of the switch.
Drawings
FIG. 1 is a circuit diagram of a single super-surface pixel cell array of the present invention.
Fig. 2 is a schematic structural diagram of a single super-surface pixel unit in an embodiment of the present invention.
FIG. 3 is a schematic structural diagram of a single subunit vortex optical super-surface generator in an embodiment of the present invention.
FIG. 4 is a schematic diagram illustrating placement of sub-wavelength antenna layers in a single super-surface pixel unit according to an embodiment of the present invention.
FIG. 5 shows the reflectivity R of cross polarization in the crystalline and amorphous states of a single pixel cell in an embodiment of the inventioncrossWith respect to the wavelength lambda.
Fig. 6 shows the relationship between the cross-polarization ratio PCR of a single pixel unit in the crystalline state and the amorphous state and the wavelength λ.
FIG. 7a is a diagram of the light field of a single pixel unit of the present invention observed at a distance of 3.5 μm from the super-surface in the amorphous state.
FIG. 7b is a phase diagram of a single pixel cell of the present invention observed at 3.5 μm from the super-surface in the amorphous state for cross-polarized portions.
FIG. 7c is a diagram of the light field of a single pixel cell of the present invention in the crystalline state, viewed at 3.5 μm from the super-surface, for cross-polarization.
FIG. 7d is a phase diagram of a single pixel cell of the present invention in the crystalline state, viewed 3.5 μm from the super-surface, in cross-polarized mode.
Reference numerals: 1. the antenna comprises a metal reflecting layer, a metal insulating medium layer, a metal phase change medium layer, a metal sub-wavelength antenna layer and a metal phase change medium layer, wherein the metal reflecting layer 2 is an insulating medium layer, 3 is a phase change medium layer, and 4 is a sub-wavelength antenna layer.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the present invention, and the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, other embodiments obtained by persons of ordinary skill in the art without any creative effort belong to the protection scope of the present invention.
First, the design principle of the present invention is explained:
the vortex reconfigurable spatial light modulator based on the geometric phase, the sub-wavelength antenna array utilizes the geometric phase, the adjustment and control of the optical wavefront phase are realized by changing the antenna rotation angle, when a beam of circularly polarized light enters, two beams of reflected light with opposite rotation directions are generated, so that polarization conservation scattering which is the same as the rotation direction of the incident light is generated, namely co-polarization, and cross polarization scattering which is opposite in rotation direction is generated, namely cross polarization, only the cross polarization part carries the geometric phase, so that the ratio of the generated geometric phase can be reflected through the reflectivity and cross polarization rate of the cross polarization, and the ratio of the generated helical phase can be reflected, wherein R is the ratio of the generated helical phase, and R is the ratio of the generated geometric phasecross＝Wcross/Wi，Rco＝Wco/Wi，PCR＝Rcorss/(Rcorss+Rco)，WcrossRepresenting the energy of the cross-polarized part, WiRepresenting the energy of the incident wave, WcoRepresenting the energy of the co-polarized part, PCR representing the cross-polarizability, RcrossA phase distribution of 0-2 pi along the angular direction is achieved in the meta-surface, representing the reflectance of the cross-polarization, and a helical phase is achieved when the cross-polarization is large.
The invention relates to application of a geometric phase super-surface in a dynamic vortex phase or reconfigurable vortex optical rotation spatial modulator, and particularly provides a vortex optical spatial modulator based on a geometric phase super-surface. And the super surface pixel unit is very thin and can be similar to a two-dimensional plane, so that the volume of the device can be greatly reduced.
Fig. 1 is an array scheme of an embodiment of the present invention, in which super-surface pixel units are controlled by TFT field effect transistors, where gates, sources, and drains of TFTs are respectively connected to row electrodes, column electrodes, and super-surface pixel units, each super-surface pixel unit can be independently addressed and controlled, a certain super-surface pixel unit is gated by the row electrodes and the column electrodes as row line and column line addressing respectively to realize local electromagnetic wave control, a phase change medium layer is electrically activated to realize transition between a crystalline state and an amorphous state, when the phase change medium layer is in an amorphous state, heating to a temperature exceeding a crystallization temperature can cause a phase change to the crystalline state, which can generally apply a lower voltage drop to the phase change medium layer to realize the transition, and when the phase change medium layer is in the amorphous state, heating to a melting temperature needs to apply a short-time large voltage to change the phase change medium layer. This embodiment is a reflective spatial light modulator that implements an electrical addressing because the electrical excitation implements the transition of the phase change material state and the super surface pixel cell is a MIM structured reflective super surface.
Fig. 2 is a schematic diagram of a super-surface pixel unit structure according to one embodiment of the present invention, fig. 3 is a super-surface structure of a single period in fig. 2, the vortex reconfigurable spatial light modulator based on a geometric phase super-surface is composed of a plurality of super-surface pixel units arranged in an M × M array, each super-surface pixel unit includes N × N sub-unit vortex optical super-surface generators arranged in an array, each sub-unit vortex optical super-surface generator can independently realize dynamic reconfiguration of a sub-beam spiral phase, and each sub-unit vortex optical super-surface generator includes a sub-wavelength antenna layer 4, a phase change dielectric layer 3, an insulating dielectric layer 2, and a metal reflective layer 1 arranged from top to bottom.
In the invention, the material of the sub-wavelength antenna layer 4 is noble metal, and the material of the phase change dielectric layer 3 is Ge2Sb2Te5The insulating medium layer 2 is made of SiO2The material of the metal reflecting layer 1 is noble metal. In one embodiment of the present invention, gold is used for the material of the sub-wavelength antenna layer 4 and the metal reflective layer 1.
In one embodiment of the present invention, the thickness of the phase change medium layer 3 is 0.03-0.07 μm, and the length and width of the phase change medium layer are consistent with those of the insulating medium layer 2 and the metal reflective layer 1.
In one embodiment of the present invention, the thicknesses h1 and h2 of the metal reflective layer 1 and the insulating medium layer 2 are 0.1 μm, the thickness h3 of the phase change medium layer 3 is 0.07 μm, the thicknesses h of the sub-wavelength antenna layers 4 are 0.07 μm, the lengths L are 0.4 μm, the widths W are 0.2 μm, and the period T is 0.5 μm, all the sub-wavelength antenna layers in each super-surface pixel unit are arranged as shown in fig. 4, it can be seen that the single super-surface pixel unit is a square, the side length is 5.5 μm, and the sub-wavelength antenna is rotated at an angle pi (in this embodiment, each sub-wavelength antenna layer is rectangular, and the antenna is rotated at an angle of a rectangle, that is 180 degrees, where a coordinate can be constructed in fig. 4, the hollow place without a rectangle is the origin, the rotation angles along the x axis are not the same, and they are phase-periodic arrangements according to the principle of geometry, the reflected light is distributed gradually along the angular direction in the plane, which meets the phase of 0-2 pi, and the spiral phase distribution is realized. The phase change dielectric layer 3, the insulating dielectric layer 2 and the metal reflecting layer 1 are all just as long as the antenna array, as shown in fig. 2.
In one embodiment of the invention, each subunit vortex optical super-surface generator can independently realize the switching effect of '1' (on state) and '0' (off state) with or without vortex, and the obtained R is simulated on FDTDcorssThe relationship with the incident light wavelength λ is shown in FIG. 5, which reflects the magnitude of cross-polarized reflectivity, while FIG. 6 shows the relationship of cross-polarization ratio, R, with respect to the wavelength, and the cross-polarization ratio, PCRcrossAnd PCR are high to ensure that the majority of the geometric phase carried in the reflected light is, as can be seen from fig. 5 and 6, when the phase change material is amorphousWhen the state is converted into the crystalline state, the resonance peak is red-shifted, the height is reduced, and the switching effect can occur through the frequency shift. R in amorphous state in 3-4 μm bandcrossAnd the PCR value is much higher than the R in the crystalline statecrossAnd PCR value, and about 3.5 μm, amorphous RcrossCan reach 0.92, crystalline state is lower than 0.03, amorphous PCR can reach 0.99 at about 3.5 mu m, crystalline state is about 0.03, and the switch effect is most obvious at the moment.
Because the geometric phase is discrete, a full continuous vortex phase is realized according to the working wavelength, the sub-wavelength antenna is required to be as small as possible, and the period is also required to be as small as possible. Therefore, in one embodiment of the present invention, the length L of each sub-wavelength antenna is 0.4 μm, the width W is 0.2 μm, the period T is 0.5 μm, and the thickness is determined according to the operating wavelength, and the embodiment is most obvious when the thickness h1 h2 h 0.1 μm, h3 h 0.07 μm, and h 0.07 μm is the thickness of the switching effect at 3.5 μm, and when GST is amorphous, the optical field (fig. 7a) and the phase (fig. 7b) of the reflected light cross polarization portion are observed by FDTD simulation, and it can be seen that the optical field and the phase satisfy the characteristic of optical rotation, the optical field is zero at the phase singular point, and the phase realizes a gradual distribution of 0-2 pi along the angular direction on the two-dimensional plane and is in a spiral distribution. When GST is crystalline, then RcrossAnd PCR are small, the optical field and phase of the cross-polarized portion of the observed reflected light are shown in fig. 7c and 7d, and it is found that the phase is deflected along an angular direction after the phase change, compared to the amorphous state, and the optical field in the crystalline state is not in an order of magnitude with the optical field in the amorphous state, which results in a small vortex phase in the crystalline state. When a beam of (left-handed or right-handed) circularly polarized light hits an anisotropic super-surface, namely a subunit vortex light super-surface, two lights (left-handed and right-handed) with different directions of rotation are generated in the reflected light or transmitted light, and the opposite direction of the direction of rotation of the incident light carries a geometric phaseA small phase position corresponds to a "0" state.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (10)
1. A vortex light space modulator based on a geometric phase super surface is characterized by comprising M multiplied by M super surface pixel units which are arranged in an array mode, wherein each super surface pixel unit can independently complete generation and closing of vortex sub-beams, and further arrayed spiral phase regulation or space regulation of a vortex sub-beam array is achieved.
2. The vortex optical spatial modulator based on the geometric phase super-surface according to claim 1, wherein each super-surface pixel unit comprises a subunit vortex optical super-surface generator composed of N × N sub-wavelength antennas arranged in an array, each subunit vortex optical super-surface generator can independently realize dynamic reconfiguration of a sub-beam spiral phase, and each subunit vortex optical super-surface generator comprises a sub-wavelength antenna layer (4), a phase change dielectric layer (3), an insulating dielectric layer (2) and a metal reflecting layer (1) arranged from top to bottom.
3. A geometric phase super-surface based vortex optical spatial modulator according to claim 2, wherein each subunit vortex optical super-surface generator can control the switching of states by electrical or optical excitation, achieving the switching effect of on and off states in the mid-infrared band.
4. A vortex optical spatial modulator based on a geometric phase metasurface according to claim 2, wherein: the working wavelength of the vortex optical rotation spatial modulator is a middle infrared band of 3-4 mu m.
5. A vortex optical spatial modulator based on a geometric phase metasurface according to claim 2, wherein: the thickness of the phase change medium layer (3) is 0.03-0.07 μm, and the length and width of the phase change medium layer are consistent with those of the insulating medium layer (2) and the metal reflecting layer (1).
6. A vortex optical spatial modulator based on a geometric phase metasurface according to claim 2, wherein: in each subunit vortex optical super-surface generator, the sub-wavelength antenna layer (4) is made of noble metal, and the phase change medium layer (3) is made of Ge2Sb2Te5The insulating medium layer (2) is made of SiO2The metal reflecting layer (1) is made of noble metal.
7. A vortex optical spatial modulator based on a geometric phase metasurface according to claim 2, wherein: the period of the sub-wavelength antenna layer (4) is smaller than the wavelength.
8. A vortex optical spatial modulator based on a geometric phase metasurface according to claim 1, wherein: after the super-surface pixel units are arrayed, each pixel is controlled through independent addressing of electric excitation loading, and electric addressing and switch control of the spatial light modulator are achieved.
9. A vortex optical spatial modulator based on a geometric phase metasurface according to claim 1, wherein: each super-surface pixel unit is square in cross section.
10. A vortex optical spatial modulator based on a geometric phase metasurface according to any of claims 1-9, wherein: the electric addressing control of the super-surface pixel unit adopts a driving array based on a TFT field effect tube, a grid electrode, a source electrode and a drain electrode of the TFT field effect tube are respectively connected with a row electrode, a column electrode and the super-surface pixel unit, and the transformation between the crystalline state and the amorphous state is realized by electrically exciting a phase change medium layer (3).
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| CN114460726A (en) * | 2022-01-30 | 2022-05-10 | 华中科技大学 | Achromatic optical zoom system based on double-layer medium super surface |
| CN114543980A (en) * | 2022-02-07 | 2022-05-27 | 北京理工大学 | Acoustic wave phase modulation and acoustic field reconstruction method based on near-field orbital angular momentum conversion |
| CN114815317A (en) * | 2022-06-28 | 2022-07-29 | 中山大学 | Imaging phase regulation and control device and method for phase change material film |
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| CN115332811A (en) * | 2022-07-26 | 2022-11-11 | 电子科技大学 | Infrared electromagnetic periodic structure with adjustable emissivity and beam anisotropic reflection function |
| CN117369028A (en) * | 2023-11-20 | 2024-01-09 | 重庆邮电大学空间通信研究院 | Sb based on geometric phase 2 Se 3 -SiO 2 Reconfigurable beam switching supersurface |
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| CN114460726A (en) * | 2022-01-30 | 2022-05-10 | 华中科技大学 | Achromatic optical zoom system based on double-layer medium super surface |
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| CN114543980A (en) * | 2022-02-07 | 2022-05-27 | 北京理工大学 | Acoustic wave phase modulation and acoustic field reconstruction method based on near-field orbital angular momentum conversion |
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| CN114815317A (en) * | 2022-06-28 | 2022-07-29 | 中山大学 | Imaging phase regulation and control device and method for phase change material film |
| CN115000716A (en) * | 2022-06-28 | 2022-09-02 | 郑州航空工业管理学院 | Anti-counterfeiting and information encryption system and method based on super-surface heat radiation modulator |
| CN115332811A (en) * | 2022-07-26 | 2022-11-11 | 电子科技大学 | Infrared electromagnetic periodic structure with adjustable emissivity and beam anisotropic reflection function |
| WO2025036199A1 (en) * | 2023-08-15 | 2025-02-20 | Huawei Technologies Co., Ltd. | Spatial light modulation device and wavelength selective switch |
| CN117369028A (en) * | 2023-11-20 | 2024-01-09 | 重庆邮电大学空间通信研究院 | Sb based on geometric phase 2 Se 3 -SiO 2 Reconfigurable beam switching supersurface |
| CN117369028B (en) * | 2023-11-20 | 2024-05-17 | 重庆邮电大学空间通信研究院 | Sb based on geometric phase2Se3-SiO2Reconfigurable beam switching supersurface |
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