Multi-band compatible programmable thermal radiator based on indium antimony telluride and application method

Abstract

A multi-band compatible programmable thermal radiator based on indium antimony telluride and an application method belong to the technical field of micro-nano photonic devices. The present invention aims to solve the problem that the thermal radiation characteristics of existing thermal radiators have a small control amplitude and a narrow control wavelength range. The controller is composed of a plurality of square control monomers periodically arranged on a silicon dioxide substrate; each square control monomer is a four-layer planar laminated structure, including, from bottom to top, a silver metal layer, an intermediate dielectric layer, an amorphous phase change material layer and a dielectric anti-reflection layer; the dielectric anti-reflection layer includes four sub-layers, and the material of each sub-layer is one of gallium arsenide, germanium and zinc sulfide; the material and thickness of the intermediate dielectric layer and each sub-layer and the thickness of the amorphous phase change material layer are determined by optimization to reflect a specific target color; the area ratio of the grating structure crystal phase change interval in the periodic structure is determined according to the infrared dual-band emissivity target value. The present invention can be used for visible-infrared multi-band compatible thermal camouflage of the target environment.

Description

Technical Field

[0001] The invention relates to a visible-infrared multi-band compatible programmable thermal radiator based on indium antimony telluride and an application method, belonging to the technical field of micro-nano photonic devices. Background Art

[0002] It is of great significance to the military and industrial fields to enable active control devices to actively control color characteristics and infrared thermal emission characteristics like animals in nature. For a long time, materials and devices that can achieve compatible control of spectral radiation characteristics in the visible band and infrared band have been one of the key research areas, especially in the field of national defense.

[0003] In recent years, volatile phase change materials such as VO2 and electrochemical materials such as liquid crystal and WO3 have been used in the active regulation of radiation characteristics. However, current spectral regulation materials or devices usually only regulate a single band, making it difficult to achieve visible-infrared multi-band compatible characteristic regulation. Therefore, the development of visible-infrared multi-band compatible programmable optical materials and devices with simple driving mechanisms, ultra-wide regulation spectral ranges, and large-scale thermal radiation characteristic change capabilities is a necessary condition for the widespread application of active regulation devices. Summary of the invention

[0004] In view of the problems that the thermal radiation characteristics of existing devices with adjustable thermal radiation characteristics have a small adjustment range and a narrow adjustment wavelength range, the present invention provides a multi-band compatible programmable thermal radiator based on indium antimony telluride and an application method.

[0005] The multi-band compatible programmable thermal radiator based on indium antimony telluride of the present invention is composed of a plurality of square control monomers periodically arranged on a silicon dioxide substrate, wherein the plurality of square control monomers are arranged to form a rectangular array;

[0006] Each square control monomer is a four-layer planar stacked structure, including, from bottom to top, a silver metal layer, an intermediate dielectric layer, an amorphous phase In3SbTe2 phase change material layer, and a dielectric anti-reflection layer; the dielectric anti-reflection layer includes four sub-layers, and the material of each sub-layer is one of gallium arsenide, germanium and zinc sulfide;

[0007] For each square control monomer, optimize it with the goal of presenting the target color in the visible band and having the maximum spectral emissivity control range in the infrared bands of 3-5 microns and 8-14 microns, and determine the material and thickness of the intermediate dielectric layer and each sub-layer, as well as the thickness of the amorphous In3SbTe2 phase change material layer;

[0008] The amorphous phase In3SbTe2 phase change material layer is extended in the middle section to form a grating structure crystalline phase In3SbTe2 phase change interval by laser direct writing excitation source heating; the grating structure crystalline phase In3SbTe2 phase change interval is heated to the melting temperature by high energy instantaneous laser and then cooled to form an amorphous phase In3SbTe2 phase change material layer;

[0009] For each square control monomer, the area ratio of the crystalline In3SbTe2 phase change range of the grating structure relative to the amorphous In3SbTe2 phase change material layer is determined according to the spectral emissivity target value.

[0010] According to the multi-band compatible programmable thermal radiator based on InSbTe of the present invention, the thickness of the silver metal layer is at least 100 nanometers.

[0011] According to the multi-band compatible programmable thermal radiator based on indium antimony telluride of the present invention, the transmittance of the square control monomer is 0 in the infrared bands of 3-5 microns and 8-14 microns, the sum of the spectral absorptivity and the reflectivity is 1, and the spectral absorptivity is the same as the spectral emissivity.

[0012] According to the multi-band compatible programmable thermal radiator based on indium antimony telluride of the present invention, the period of the square control monomer is 2 microns; the material of the intermediate dielectric layer is one of gallium arsenide, germanium or zinc sulfide.

[0013] According to the multi-band compatible programmable thermal radiator based on indium antimony telluride of the present invention, the silver metal layer, the intermediate dielectric layer, the amorphous phase In3SbTe2 phase change material layer and the dielectric anti-reflection layer are sequentially prepared on a silicon dioxide substrate by a magnetron sputtering method.

[0014] According to the multi-band compatible programmable thermal radiator based on indium antimony telluride of the present invention, by adjusting the area ratio of the phase change interval of the grating structure crystal phase In3SbTe2, the spectral emissivity of each square control monomer in the infrared bands of 3-5 microns and 8-14 microns can be continuously controlled between 0-1.

[0015] According to the multi-band compatible programmable thermal radiator based on indium antimony telluride of the present invention, the wavelength range of incident light of the square control monomer is 360-830 nanometers in the visible band, and 3-5 micrometers and 8-14 micrometers in the infrared band.

[0016] The application method of the multi-band compatible programmable heat radiator based on indium antimony telluride of the present invention is implemented based on the multi-band compatible programmable heat radiator based on indium antimony telluride, comprising:

[0017] Step 1: A multi-band thermal camouflage device is formed by combining multiple programmable thermal emission controllers; the material and thickness of the intermediate dielectric layer and each sub-layer and the thickness of the amorphous In3SbTe2 phase change material layer are set for each programmable thermal emission controller according to the thermal camouflage target color and the maximum spectral emissivity control range in the infrared bands of 3-5 microns and 8-14 microns;

[0018] Step two, according to the spectral emissivity target value, adjust the area ratio of the grating structure crystal phase In3SbTe2 phase change range in each programmable thermal emission controller, so that the spectral emissivity of each programmable thermal emission controller in the infrared bands of 3-5 microns and 8-14 microns approaches the spectral emissivity target value, thereby realizing the camouflage of multi-band thermal camouflage devices.

[0019] According to the application method of the multi-band compatible programmable thermal radiator based on indium antimony telluride of the present invention, in step 1, the thermal camouflage target color is represented by the coordinates in the CIE1931 xy chromaticity system:

[0020]

[0021] Where x is the abscissa of the thermal camouflage target color in the CIE1931xy chromaticity system, y is the ordinate of the thermal camouflage target color in the CIE1931xy chromaticity system; X is the stimulus value of red among the three primary colors, Y is the stimulus value of green among the three primary colors, and Z is the stimulus value of blue among the three primary colors;

[0022]

[0023] Where λ is the incident light wavelength of the square control monomer, S(λ) is the standard spectral radiation energy distribution of the D65 light source, and R(λ) is the spectral reflectivity of the thermal camouflage environment background or thermal camouflage object in the visible band; and are the standard matching functions for the three primary color stimulus values ​​respectively.

[0024] According to the application method of the multi-band compatible programmable thermal radiator based on indium antimony telluride of the present invention, the spectral emissivity target value in step 2 is obtained by inverting the normalized radiation intensity; the calculation method of the normalized radiation intensity is:

[0025]

[0026] Where I norm is the normalized radiation intensity of each programmable thermal emission controller, I min is the minimum radiation intensity of all programmable thermal emission controllers in the multi-band thermal camouflage device; I maxis the maximum radiation intensity of all programmable thermal emission controllers in the multi-band thermal camouflage device; I is the radiation intensity of each programmable thermal emission controller:

[0027]

[0028] Where ε(λ) is the spectral emissivity of the programmable thermal emission controller, T is the temperature of the programmable thermal emission controller, and λ min is the initial wavelength of the incident light, λ max is the cut-off wavelength of the incident light, c1 is the first radiation constant, and its value is 3.7419×10 -16 W·m 2 ; c2 is the second radiation constant, with a value of 1.4388×10 -2 m.K.

[0029] Beneficial effects of the invention: Based on the optical multimodal coupling effect, the invention realizes the compatibility of thermal camouflage devices in visible color characteristics and thermal emission regulation in infrared multi-bands, and can be used for thermal camouflage in target environments. The thermal emission regulator can not only show most color characteristics, but also ensure a very high regulation range in the infrared detection band; its visible band color characteristics and infrared thermal emission characteristics can be independently regulated.

[0030] The controller of the present invention optimizes the material composition arrangement and thickness of the top four-layer laminated anti-reflection layer, and according to the optical multi-modal coupling theory, can achieve almost all visible band color characteristics without affecting the infrared control ability. By changing the size f of the phase change area of ​​the device, the ultra-large-scale active control of the emissivity in the multi-band ultra-wide spectral range is achieved, which has the advantages of large control amplitude, wide control wavelength range and good control stability, giving the multi-band emissivity control device great initiative.

[0031] The regulator described in the present invention has a simple structure and is easy to prepare. The device can be prepared and the emission characteristics can be regulated by using magnetron sputtering equipment and laser or electrical excitation. It provides a promising method and platform for regulating the emission characteristics of visible-infrared multi-band compatible thermal emitters, and provides a reference for the subsequent design and application of visible-infrared multi-band compatible programmable optical modulation devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the stacked structure of a square control monomer of the multi-band compatible programmable thermal radiator based on indium antimony telluride according to the present invention;

[0033] Figure 2 It is a schematic diagram of the phase change interval of the crystalline In3SbTe2 of the grating structure formed in the middle section of the amorphous phase In3SbTe2 phase change material layer;

[0034] Figure 3 It is a simulation result diagram of the spectral emissivity of the programmable thermal emission controller when the four sub-layers of the dielectric anti-reflection layer and the middle dielectric layer are all made of zinc sulfide; the thickness of each layer is optimized by using the genetic optimization method to ensure the maximum control range of the infrared 3-5 micron and 8-14 micron dual-band emissivity, and it is determined that the total thickness of the ZnS in the dielectric anti-reflection layer is 1.336 microns, the thickness of the amorphous phase In3SbTe2 phase change material layer is 11 nanometers, the thickness of the middle dielectric layer is 1.493 microns, and the thickness of the silver metal layer is 0.2 microns; Indicates the change in average emissivity in the infrared 3-5 micron band, It indicates the change of average emissivity in the infrared 8-14 micron band;

[0035] Figure 4 yes Figure 3 The optimized multi-band compatible programmable thermal radiator based on indium antimony telluride corresponds to the polarized average spectral emissivity cloud diagram in the 3-5 micron and 8-14 micron bands when the area ratio f of the grating structure crystal phase In3SbTe2 phase change interval changes; the white dotted lines in the figure are the positions of wavelengths of 5 microns and 8 microns;

[0036] Figure 5 It corresponds to Figure 3 Polarization-averaged average emissivity of the optimized multi-band compatible programmable thermal radiator based on InSbTe in the 3-5 μm and 8-14 μm bands at different IST phase change material layer proportions f Schematic diagram of Indicates the average emissivity in the infrared 3-5 micron band, It represents the average emissivity in the infrared 8-14 micron band;

[0037] Figure 6 yes Figure 3 The phase change result of the incident light in the cavity formed by the top layer of air / ZnS / aIST when the amorphous In3SbTe2 phase change material layer has not changed in the optimized programmable thermal emission controller; in the figure, @ indicates the wavelength position of the corresponding point;

[0038] Figure 7 yes Figure 3 The phase change results of the incident light in the cavity formed by the bottom layer aIST / zinc sulfide / silver when the amorphous In3SbTe2 phase change material layer has not changed in the optimized programmable thermal emission controller;

[0039] Figure 8 yes Figure 3The phase change result of the incident light in the cavity formed by the top layer of air / ZnS / cIST after the phase change of the amorphous In3SbTe2 phase change material layer in the optimized programmable thermal emission controller. In the figure, Air represents air and Cavity represents cavity.

[0040] Fig. 9 yes Figure 3 The phase change results of the incident light in the cavity formed by the bottom cIST / zinc sulfide / silver after the phase change of the amorphous In3SbTe2 phase change material layer in the optimized programmable thermal emission controller;

[0041] Fig.10 The genetic optimization method is used to ensure that the 3-micron to 5-micron and 8-micron to 14-micron bands have a high average emissivity control capability. By changing the thickness of each layer and the material composition of each dielectric layer, the device can achieve a visible light band color range without IST phase change. The red star symbol in the figure represents the labeled example samples Eg1 to Eg6 extracted from it; Coordinate x in the figure represents the x-coordinate, and Coordinate y represents the y-coordinate;

[0042] Fig.11 yes Fig.10 The color range of the visible light band of the controller with the structure shown after the IST layer has completely changed phase; the red star symbol indicates Fig.10 The color results after phase change corresponding to the example samples Eg1 to Eg6 are marked in the middle;

[0043] Fig.12 yes Fig.10 and Fig.11 The programmable thermal emission controller of the present invention shown in Example 1 (Eg1) is a graph showing the calculation results of the visible light spectrum reflectance under normal incident non-polarized light when the amorphous In3SbTe2 phase change material layer is all in the amorphous phase (aIST) and all in the crystalline phase (cIST); the legend in the figure shows the CIE1931 chromaticity diagram coordinate values ​​when the amorphous In3SbTe2 phase change material layer is all in the amorphous phase (aIST) and all in the crystalline phase (cIST);

[0044] Fig.13 yes Fig.10 and Fig.11 The calculation result diagram of the visible light spectral reflectance of the programmable thermal emission controller of the present invention shown in Example 2 (Eg2) when the amorphous phase In3SbTe2 phase change material layer is all amorphous phase (aIST) and all crystalline phase (cIST) under normal incident non-polarized light;

[0045] Fig.14 yes Fig.10 and Fig.11The calculation result diagram of the visible light spectral reflectance of the programmable thermal emission controller of the present invention shown in Example 3 (Eg3) when the amorphous phase In3SbTe2 phase change material layer is all amorphous phase (aIST) and all crystalline phase (cIST) under normal incident non-polarized light;

[0046] Fig.15 yes Fig.10 and Fig.11 The calculation result diagram of the visible light spectral reflectance of the programmable thermal emission controller of the present invention shown in Example 4 (Eg4) when the amorphous phase In3SbTe2 phase change material layer is all amorphous phase (aIST) and all crystalline phase (cIST) under normal incident non-polarized light;

[0047] Fig.16 yes Fig.10 and Fig.11 The calculation result diagram of the visible light spectral reflectance of the programmable thermal emission controller of the present invention shown in Example 5 (Eg5) when the amorphous phase In3SbTe2 phase change material layer is all amorphous phase (aIST) and all crystalline phase (cIST) under normal incident non-polarized light;

[0048] Fig.17 yes Fig.10 and Fig.11 The calculation result diagram of the visible light spectral reflectance of the programmable thermal emission controller of the present invention shown in Example 6 (Eg6) when the amorphous phase In3SbTe2 phase change material layer is all amorphous phase (aIST) and all crystalline phase (cIST) under normal incident non-polarized light;

[0049] Fig.18 yes Fig.10 and Fig.11 The infrared spectral emissivity calculation result diagram of the programmable thermal emission controller of the present invention shown in Example 1 (Eg1) when the amorphous phase In3SbTe2 phase change material layer is all in the amorphous phase (aIST) and all in the crystalline phase (cIST) under normal incident non-polarized light in the ultra-wide band of 3-14 microns;

[0050] Fig.19 yes Fig.10 and Fig.11 The infrared spectral emissivity calculation result diagram of the programmable thermal emission controller of the present invention shown in Example 2 (Eg2) when the amorphous phase In3SbTe2 phase change material layer is all amorphous phase (aIST) and all crystalline phase (cIST) under normal incident non-polarized light in the ultra-wide band of 3-14 microns;

[0051] Fig. 20 yes Fig.10 and Fig.11The infrared spectral emissivity calculation result diagram of the programmable thermal emission controller of the present invention shown in Example 3 (Eg3) when the amorphous phase In3SbTe2 phase change material layer is all amorphous phase (aIST) and all crystalline phase (cIST) under normal incident non-polarized light in the ultra-wide band of 3-14 microns;

[0052] Fig.21 yes Fig.10 and Fig.11 The programmable thermal emission controller of the present invention shown in Example 4 (Eg4) is a graph showing the infrared spectral emissivity calculation results in the ultra-wide band of 3-14 microns under normal incident non-polarized light when the amorphous In3SbTe2 phase change material layer is all in the amorphous phase (aIST) and all in the crystalline phase (cIST);

[0053] Fig. 22 yes Fig.10 and Fig.11 The infrared spectral emissivity calculation result diagram of the programmable thermal emission controller of the present invention shown in Example 5 (Eg5) when the amorphous phase In3SbTe2 phase change material layer is all in the amorphous phase (aIST) and all in the crystalline phase (cIST) under normal incident non-polarized light in the ultra-wide band of 3-14 microns;

[0054] Fig.23 yes Fig.10 and Fig.11 The infrared spectral emissivity calculation result diagram of the programmable thermal emission controller of the present invention shown in Example 6 (Eg6) when the amorphous phase In3SbTe2 phase change material layer is all amorphous phase (aIST) and all crystalline phase (cIST) under normal incident non-polarized light in the ultra-wide band of 3-14 microns;

[0055] Fig.24 yes Fig.10 and Fig.11 The programmable thermal emission controller of the present invention shown in Example 1 (Eg1) shows a cloud diagram of the polarized average spectral emissivity ε(λ) in the 3-5 μm and 8-14 μm bands when adjusting the area ratio f of the phase transition interval of the grating structure crystal phase In3SbTe2; the white dotted lines in the figure are the positions with wavelengths of 5 μm and 8 μm;

[0056] Fig.25 yes Fig.10 and Fig.11 The programmable thermal emission controller of the present invention shown in Example 1 (Eg1) controls the area ratio f of the phase transition interval of the grating structure crystal phase In3SbTe2, and the average polarization average emissivity in the 3-5 micron and 8-14 micron bands Schematic diagram of

[0057] Fig.26 yes Fig.10 and Fig.11 The programmable thermal emission controller of the present invention shown in Example 1 (Eg1) shows the spectral reflectance in the visible band when adjusting the area ratio f of the phase change interval of the grating structure crystal phase In3SbTe2. The right side shows the visible color characteristics corresponding to different phase change area ratios f, indicating that infrared control does not affect the color characteristics of the visible band;

[0058] Fig. 27 Yes Fig.10 and Fig.11 Schematic diagram of programmable arrangement of marking example 1-marking example 6 to form visible band color camouflage;

[0059] Fig.28 Yes Fig. 27 The phase change interval area proportion f in each color block is modulated to achieve on-demand customization of the thermal radiation characteristics between different color blocks, thereby realizing a programmable camouflage schematic diagram in the infrared 3-5 micron band;

[0060] Fig.29 Yes Fig. 27 The phase change interval area proportion f in each color block is modulated to achieve on-demand customization of the thermal radiation characteristics between different color blocks, thereby realizing a programmable camouflage schematic diagram in the infrared 8-14 micron band. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the 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.

[0062] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0063] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0064] Specific implementation method 1. Combination Figure 1 and Figure 2 As shown, the present invention provides a multi-band compatible programmable thermal radiator based on indium antimony telluride, which is composed of a plurality of square control monomers periodically arranged on a silicon dioxide substrate, and the plurality of square control monomers are arranged to form a rectangular array;

[0065] Each square control monomer is a four-layer planar stacked structure, including, from bottom to top, a silver metal layer 1, an intermediate dielectric layer 2, an amorphous phase In3SbTe2 phase change material layer 3 and a dielectric anti-reflection layer 5; the dielectric anti-reflection layer 5 includes four sub-layers, and the material of each sub-layer is one of gallium arsenide, germanium and zinc sulfide;

[0066] For each square control monomer, optimization is performed with the goal of presenting the target color in the visible band and having the maximum spectral emissivity control range in the infrared bands of 3-5 microns and 8-14 microns, and the material and thickness of the intermediate medium layer 2 and each sub-layer and the thickness of the amorphous phase In3SbTe2 phase change material layer 3 are determined; the optimization method can adopt common intelligent optimization methods, such as genetic optimization method and particle swarm optimization method, etc.;

[0067] The amorphous phase In3SbTe2 phase change material layer 3 is extended in the middle section to form a grating structure crystalline phase In3SbTe2 phase change interval 4 by laser direct writing excitation source heating; the grating structure crystalline phase In3SbTe2 phase change interval 4 is heated to the melting temperature by high energy instantaneous laser and then cooled to form the amorphous phase In3SbTe2 phase change material layer 3;

[0068] For each square control monomer, according to the spectral emissivity target value at the corresponding position, the area ratio of the grating structure crystalline phase In3SbTe2 phase change interval 4 relative to the amorphous phase In3SbTe2 phase change material layer 3 can be inverted and determined by genetic optimization and other methods.

[0069] The area ratio of the grating structure crystalline phase In3SbTe2 phase change interval 4 relative to the amorphous phase In3SbTe2 phase change material layer 3 is expressed as f:

[0070] f=L cIST / Λ,

[0071] Where L cIST represents the width of the phase transition interval of the grating structure crystal phase In3SbTe2, and Λ represents the period of the square control monomer.

[0072] The optimization design method for the programmable thermal emission controller is to set the square control monomer according to the corresponding CIE1931 chromaticity xy coordinate target value and achieve the maximum emissivity control ability in the mid-infrared 3-5 microns and far-infrared 8-14 microns. The thickness of each layer and the composition material of each dielectric layer are selected by reverse optimization design through genetic optimization algorithm, so that the device can reflect the desired color characteristics while achieving the maximum range of infrared 3-5 microns and 8-14 microns thermal emission control. The fitness function values ​​F1 and F2 of the inverse design optimization are:

[0073]

[0074]

[0075] In the formula and is the average emissivity difference before and after the phase change of the device in the 3-5 μm, 5-8 μm and 8-14 μm bands, x aim ,y aim is the coordinate value of the target color in the CIE1931 chromaticity coordinates.

[0076] The infrared detection band (3-5 microns and 8-14 microns) is one of the most important atmospheric windows for infrared detection, optical camouflage and thermal control. Non-volatile phase change materials show stable performance and huge optical contrast between amorphous and crystalline states, reflecting great potential for integration into infrared optical modulation platforms. As a non-volatile phase change material, In3SbTe2 (IST) can show metal-like properties with huge negative dielectric constant in the full infrared region in the crystalline phase (cIST), and act as a lossless dielectric medium in the infrared region in the amorphous phase (aIST), and can achieve non-volatile local phase change through laser or electrical excitation, laying the foundation for the development of continuously controlled, programmable, and large-degree-of-change mid-infrared emissivity control devices.

[0077] Furthermore, the thickness of the silver metal layer 1 is at least 100 nanometers.

[0078] As an example, the thickness of the silver metal layer 1 is selected to be 200 nanometers.

[0079] In this embodiment, the thickness of the silver metal layer 1 is much greater than its skin depth in the mid-infrared band, which can ensure that the transmittance of the square control monomer is 0 in the infrared bands of 3-5 microns and 8-14 microns, the sum of the spectral absorptivity and the reflectivity is 1, and the spectral absorptivity is the same as the spectral emissivity.

[0080] As an example structure of the infrared detection band control capability and control principle, the period of the square control monomer is 2 microns; the material of the intermediate dielectric layer 2 is one of gallium arsenide, germanium or zinc sulfide.

[0081] The materials of each layer in the middle dielectric layer 2 and the top four-layer laminated dielectric anti-reflection layer 5 can be selected as zinc sulfide. The thickness of the middle dielectric layer 2 is 1336 nanometers, the total thickness of the dielectric anti-reflection layer 5 is 1493 nanometers, and the thickness of the amorphous In3SbTe2 phase change material layer 3 is 11 nanometers.

[0082] The silver metal layer 1, the intermediate dielectric layer 2, the amorphous In3SbTe2 phase change material layer 3 and the dielectric anti-reflection layer 5 are sequentially prepared on a silicon dioxide substrate by using a magnetron sputtering method.

[0083] Experimental verification shows that by adjusting the area ratio f of the grating structure crystal phase In3SbTe2 phase change interval 4, the spectral emissivity of each square control monomer in the dual infrared bands of 3-5 microns and 8-14 microns can be continuously controlled between close to 0 and close to 1, with a sufficiently large spectral emissivity amplitude control capability. The average emissivity control amplitude of the mid-infrared detection band 3-5 microns obtained in this embodiment is 0.843, and the average emissivity control amplitude of the far-infrared detection band 8-14 microns obtained is 0.921. Figure 3 As shown, a huge mid-infrared emissivity switch is achieved.

[0084] In this embodiment, the wavelength range of the incident light of the square control monomer is 360-830 nanometers in the visible band, and 3-5 micrometers and 8-14 micrometers in the infrared band.

[0085] Combination Figure 4 and Figure 5 As shown, in this embodiment, when laser or electric excitation is applied to the amorphous phase In3SbTe2 phase change material layer 3, a grating-shaped crystalline phase In3SbTe2 phase change interval 4 can be generated in the amorphous phase In3SbTe2 phase change material layer 3. By controlling the phase change area proportion f, the average emissivity of the mid-infrared 3-5 micron band of the regulator can be continuously regulated from 0.031 (the In3SbTe2 layer is all amorphous phase) to 0.874 (the In3SbTe2 layer is all crystalline phase), and the average emissivity of the far-infrared 8-14 micron band during the regulation period can be continuously regulated from 0.039 (the In3SbTe2 layer is all amorphous phase) to 0.96 (the In3SbTe2 layer is all crystalline phase). At the same time, by using high-power laser or electric excitation to heat the crystalline phase In3SbTe2 to a molten state and then rapidly cooling it, the crystalline phase In3SbTe2 can be transformed back to the amorphous phase In3SbTe2, realizing reversible regulation.

[0086] In this embodiment, when the controller is used for infrared thermal radiation programmable camouflage, each thermal radiation modulator calculates the spectral emissivity of the camouflaged target at the corresponding position to obtain the size f of the phase change ratio of the square control monomer, thereby realizing programmable thermal camouflage in a complex camouflage environment. Using laser and electrical excitation, unit structures with different phase change ranges can be prepared in different regions within a large area, and the mid-infrared emissivity in different regions can be programmably customized according to the actual environmental requirements.

[0087] Combination Figures 6 to 9The working process and principle of the present invention in regulating infrared thermal radiation characteristics are described as follows: the multi-layer stacked structure forms two nanocavities of air / zinc sulfide / IST and IST / ZnS / Ag. When the net phase shift of the incident light in the cavity is an integer multiple of 2π, FP resonance can be stimulated to increase the absorption in the cavity. Before the phase change, the phase shifts in the two nanocavities of Air / ZnS / aIST and aIST / ZnS / Ag are integer multiples of 2π at wavelengths of 3.69μm, 5.17μm and 8.48m, which are extremely close to the calculated peak wavelengths of the emissivity of the device before the phase change of 3.697μm, 5.184μm and 8.447μm. Therefore, it can be considered that FP resonance occurs in the two cavities, but because aIST and ZnS are almost transparent media in the infrared band, only Ag produces weak absorption, so the device as a whole presents extremely weak infrared spectral emission characteristics. After the phase change, the phase shift results show that the net phase shift after 8μm in the top-layer Air / ZnS / cIST nanocavity is close to 0, which means that the top-layer ZnS in this band acts as an anti-reflection layer, resulting in the high emission characteristics of thermal radiation in the 8-14μm band. At the same time, in the top layer Air / ZnS / cIST nanocavity and cIST / ZnS / Ag nanocavity, the calculated phase shift shows that a phase shift equal to an integer multiple of 2π is generated at 4.607μm, which is close to the calculated peak wavelength of the spectral emissivity in the 3-5μm band of 4.609μm, indicating that the high emissivity at 4.609μm is generated by the FP resonance generated by the top layer Air / ZnS / cIST cavity, and the high emissivity at 3.715μm is coupled with the FP resonance mode obtained by the upper and lower nanocavities at 3.664μm and 3.601μm. Therefore, it can be determined that the optical mode coupling based on the upper and lower nanocavities leads to the device producing higher spectral thermal emission characteristics in the 3-5 micron band after the phase change. Since the optical mode coupling effect does not depend on a specific structure and material arrangement, there are a variety of material selections and arrangement structures that can achieve extremely high control amplitudes in the infrared 3-5 microns and 8-14 microns, providing a basis for the subsequent control of visible color characteristics.

[0088] In this embodiment, the regulator is used for visible color programmable camouflage by changing the thickness of each layer and the material composition of each dielectric layer through optimized design on the basis of ensuring that each thermal radiation modulator has a high average emissivity control capability from 3 microns to 5 microns and from 8 microns to 14 microns. The resulting device can achieve the desired visible light band color characteristics without IST phase change.

[0089] Combination Figures 10 to 23 The invention is capable of regulating the thermal radiation characteristics in the visible-infrared multi-band compatibility: Fig.10 and Fig.11The results show that the visible color characteristics can be achieved based on different dielectric layer material combinations before and after the phase change of the In3SbTe2 layer and a large adjustment range in the infrared detection band. It can be seen that almost all color characteristics can be achieved through this method. Since the optical characteristics of In3SbTe2 in the visible band change little and the thickness is thin, the visible color characteristics before and after the phase change will not change. Figures 12 to 17 The visible band spectral reflectance R(λ) of 6 schematic devices with different visible color characteristics and their coordinates and color characteristics in the CIE1931 coordinate diagram are shown. Figures 18 to 23 for Figures 12 to 17 The calculated results of the infrared spectral thermal emission characteristics of the device shown in the figure all show extremely high regulation potential in the infrared detection band. It can be seen that the visible-infrared multi-band compatible Indium Antimony Telluride programmable thermal emission controller based on optical multimodal coupling has achieved visible-infrared multi-band compatibility characteristics.

[0090] Combination Fig.24 and Fig.25 In this embodiment, it is shown that when the example device 1 is applied to the amorphous phase In3SbTe2 phase change material layer 3 by laser or electrical excitation, a grating-shaped crystalline phase In3SbTe2 phase change interval 4 can be generated in the amorphous phase In3SbTe2 phase change material layer 3. By controlling the size f of the phase change area, the average emissivity of the mid-infrared 3-5 micron band of the regulator can be continuously adjusted from 0.03 (the In3SbTe2 layer is all amorphous phase) to 0.88 (the In3SbTe2 layer is all crystalline phase), and the average emissivity of the far-infrared 8-14 micron band during the regulation period can be continuously adjusted from 0.034 (the In3SbTe2 layer is all amorphous phase) to 0.955 (the In3SbTe2 layer is all crystalline phase). At the same time, by using high-power laser or electrical excitation to heat the crystalline phase In3SbTe2 to a molten state and then rapidly cooling it, the crystalline phase In3SbTe2 can be transformed back to the amorphous phase In3SbTe2, realizing reversible regulation.

[0091] In summary, the optical multimodal coupling effect of the programmable thermal emission controller described in this embodiment does not depend on a specific optical structure, and the same optical characteristics can be achieved by adopting different structures; that is, in theory, similar infrared spectral characteristics can be achieved by optimizing the material composition arrangement and thickness of the top four dielectric anti-reflection layers 5. The top four dielectric anti-reflection layers 5 with different material composition arrangements and thicknesses can also show different color characteristics in the visible light range, so different colors can be achieved while ensuring that the infrared characteristics remain unchanged. Since the dielectric function of indium antimony telluride does not change much before and after the phase change in the visible band, and the reflection characteristics of the visible light band before and after the phase change are relatively thin, the color characteristics of the device in the visible band can be guaranteed to remain unchanged when the infrared thermal emission characteristics are controlled by changing the phase change ratio, thereby achieving the characteristics of visible-infrared multi-band spectral characteristics that do not affect each other and are compatible.

[0092] Specific implementation method 2: Combination Figure 1 and Figure 2 As shown, the present invention provides an application method of a multi-band compatible programmable thermal radiator based on indium antimony telluride, which can realize visible-infrared multi-band compatible thermal camouflage based on optical multimodal coupling, and is realized based on the multi-band compatible programmable thermal radiator based on indium antimony telluride described in the specific implementation mode 1, including:

[0093] Step 1: A multi-band thermal camouflage device is formed by combining multiple programmable thermal emission controllers; the material and thickness of the intermediate medium layer 2 and each sub-layer and the thickness of the amorphous In3SbTe2 phase change material layer 3 are set for each programmable thermal emission controller according to the thermal camouflage target color and the maximum spectral emissivity control range in the infrared bands of 3-5 microns and 8-14 microns;

[0094] Step two, according to the spectral emissivity target value, adjust the area ratio of the grating structure crystal phase In3SbTe2 phase change interval 4 in each programmable thermal emission controller, so that the spectral emissivity of each programmable thermal emission controller in the infrared bands of 3-5 microns and 8-14 microns approaches the spectral emissivity target value, thereby realizing the camouflage of multi-band thermal camouflage devices.

[0095] In step one, the thickness of each dielectric layer and material selection of the thermal emission controller in each color block are determined based on the optimized design to ensure that the devices in different color blocks have greater controllable capabilities in the infrared detection bands of 3-5 microns and 8-14 microns, so that they can reflect different color characteristics as needed in the visible band, thereby realizing programmable color camouflage in the visible band.

[0096] In step 2, since the infrared detector imaging will normalize the maximum and minimum values ​​of the received thermal radiation density, the area ratio f of the grating structure crystal phase In3SbTe2 phase change interval 4 is adjusted, the amorphous phase In3SbTe2 phase change material layer 3 at the corresponding position is heated and transformed into the grating structure crystal phase In3SbTe2 phase change interval 4 or the grating structure crystal phase In3SbTe2 phase change interval 4 is reheated and then cooled, so that the normalized thermal emission characteristics of different color blocks can be controlled on demand, thereby realizing camouflage of programmable infrared thermal emission characteristics.

[0097] Furthermore, in step 1, the thermal camouflage target color is represented by coordinates in the CIE1931 xy colorimetric system:

[0098]

[0099] Where x is the abscissa of the thermal camouflage target color in the CIE1931xy chromaticity system, y is the ordinate of the thermal camouflage target color in the CIE1931xy chromaticity system; X is the stimulus value of red among the three primary colors, Y is the stimulus value of green among the three primary colors, and Z is the stimulus value of blue among the three primary colors;

[0100]

[0101] Where λ is the incident light wavelength of the square control monomer, S(λ) is the standard spectral radiation energy distribution of the D65 light source, and R(λ) is the spectral reflectivity of the thermal camouflage environment background or thermal camouflage object in the visible band; and are the standard matching functions for the three primary color stimulus values ​​respectively.

[0102] In step 2, the target value of spectral emissivity is obtained by inverting the normalized radiation intensity; the calculation method of normalized radiation intensity is:

[0103]

[0104] Where I norm is the normalized radiation intensity of each programmable thermal emission controller, I min is the minimum radiation intensity of all programmable thermal emission controllers in the multi-band thermal camouflage device; I max is the maximum radiation intensity of all programmable thermal emission controllers in the multi-band thermal camouflage device; I is the radiation intensity of each programmable thermal emission controller:

[0105]

[0106] Where ε(λ) is the spectral emissivity of the programmable thermal emission controller, T is the temperature of the programmable thermal emission controller, and λ minis the initial wavelength of the incident light, λ max is the cut-off wavelength of the incident light, c1 is the first radiation constant, and its value is 3.7419×10 -16 W·m 2 ; c2 is the second radiation constant, with a value of 1.4388×10 -2 m.K. Specific embodiment:

[0108] First, the thickness of each layer and the material selection of the dielectric layer of multiple indium antimony telluride programmable visible-infrared multi-band compatible thermal emission controllers based on optical multimodal coupling are optimized and designed. On the basis of ensuring that they have a large controllable ability in the infrared detection band of 3-5 microns and 8-14 microns, multiple devices can reflect different color characteristics as needed in the visible band. Then, the obtained devices are used as color blocks of thermal camouflage equipment and arranged and combined into camouflage devices with visible color camouflage characteristics. Fig.10 and Fig.11 As an example, the structures of Examples 1 to 6 in the above-mentioned examples can be arranged as required to form the following Fig. 27 The HIT pattern shown can also be arranged into a more confusing pattern as required.

[0109] Through Fig. 27 By adjusting the proportion f of the crystalline In3SbTe2 phase change region in each color block, different color blocks can exhibit different thermal radiation characteristics. By design, when the proportion f of the phase change region in Examples 1 to 6 is 0.5, 0.1, 0.75, 0.85, 0.85, and 0.2 respectively, Fig. 27 The normalized thermal radiation density images of the thermal camouflage device in the 3-5 micron and 8-14 micron detectors are shown as follows Fig.28 and Fig.29 As shown, a more confusing infrared image can also be achieved by changing the phase change area proportion f of different color blocks.

[0110] Combination Fig.26 As shown in the figure, the colors of the square regulatory monomers corresponding to different values ​​of the phase change interval area ratio f indicate that when the phase change interval area ratio f is changed, the color characteristics of the square regulatory monomers can remain unchanged.

[0111] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that the features described in conjunction with a single embodiment may be used in other described embodiments.

Claims

1. A multi-band compatible programmable thermal radiator based on indium antimony telluride, characterized in that: It is composed of a plurality of square regulating monomers periodically arranged on a silicon dioxide substrate, wherein the plurality of square regulating monomers are arranged to form a rectangular array; Each square control monomer is a four-layer planar stacked structure, comprising, from bottom to top, a silver metal layer (1), an intermediate dielectric layer (2), an amorphous phase In3SbTe2 phase change material layer (3) and a dielectric anti-reflection layer (5); the dielectric anti-reflection layer (5) comprises four sub-layers, and the material of each sub-layer is one of gallium arsenide, germanium and zinc sulfide; For each square control monomer, optimization is performed with the goal of presenting a target color in the visible band and having a maximum spectral emissivity control range in the infrared bands of 3-5 microns and 8-14 microns, and the material and thickness of the intermediate dielectric layer (2) and each sub-layer and the thickness of the amorphous In3SbTe2 phase change material layer (3) are determined; The amorphous phase In3SbTe2 phase change material layer (3) is extended in the middle section to form a grating structure crystalline phase In3SbTe2 phase change interval (4) by using a laser direct writing excitation source heating method; the grating structure crystalline phase In3SbTe2 phase change interval (4) is heated to a melting temperature by using a high-energy instantaneous laser and then cooled to form an amorphous phase In3SbTe2 phase change material layer (3); For each square control monomer, the area ratio of the grating structure crystalline phase In3SbTe2 phase change interval (4) relative to the amorphous phase In3SbTe2 phase change material layer (3) is determined according to the spectral emissivity target value; The square control monomer is designed according to the corresponding CIE1931 chromaticity xy coordinate target value and the two goals of achieving the maximum emissivity control ability in the mid-infrared 3-5 microns and the far-infrared 8-14 microns. The thickness of each layer and the composition material of each dielectric layer are selected through the reverse optimization design of the genetic optimization algorithm, so that the device can reflect the desired color characteristics while achieving the maximum range of infrared 3-5 microns and 8-14 microns thermal emission control. The fitness function values ​​F1 and F2 of the inverse design optimization are: In the formula and is the average emissivity difference before and after the phase change of the device in the 3-5 μm, 5-8 μm and 8-14 μm bands, x aim ,y aim is the expected coordinate value of the target color in the CIE1931 chromaticity coordinates; x is the abscissa of the thermal camouflage target color in the CIE1931xy chromaticity system, and y is the ordinate of the thermal camouflage target color in the CIE1931xy chromaticity system.

2. The multi-band compatible programmable thermal radiator based on indium antimony telluride according to claim 1, characterized in that: The thickness of the silver metal layer (1) is at least 100 nanometers.

3. The multi-band compatible programmable thermal radiator based on indium antimony telluride according to claim 1, characterized in that: The transmittance of the square control monomer is 0 in the infrared bands of 3-5 microns and 8-14 microns, the sum of the spectral absorptivity and the reflectivity is 1, and the spectral absorptivity is the same as the spectral emissivity.

4. The multi-band compatible programmable thermal radiator based on indium antimony telluride according to claim 1, characterized in that: The period of the square control monomer is 2 micrometers; the material of the intermediate dielectric layer (2) is one of gallium arsenide, germanium or zinc sulfide.

5. The multi-band compatible programmable thermal radiator based on indium antimony telluride according to claim 1, characterized in that: A silver metal layer (1), an intermediate dielectric layer (2), an amorphous phase In3SbTe2 phase change material layer (3) and a dielectric anti-reflection layer (5) are sequentially prepared on a silicon dioxide substrate by using a magnetron sputtering method.

6. The multi-band compatible programmable thermal radiator based on indium antimony telluride according to claim 1, characterized in that: By adjusting the area ratio of the In3SbTe2 phase change interval (4) of the grating structure crystal phase, the spectral emissivity of each square control monomer in the infrared bands of 3-5 microns and 8-14 microns can be continuously controlled between 0 and 1.

7. The multi-band compatible programmable thermal radiator based on Indium Antimony Telluride according to claim 1, characterized in that: The wavelength range of incident light for the square control monomer is 360-830 nanometers in the visible band, and 3-5 microns and 8-14 microns in the infrared band.

8. An application method of a multi-band compatible programmable thermal radiator based on indium antimony telluride, characterized in that: A multi-band compatible programmable thermal radiator based on indium antimony telluride according to any one of claims 1 to 7, characterized in that it includes: Step 1: A multi-band thermal camouflage device is formed by combining a plurality of programmable thermal emission controllers; the material and thickness of the intermediate dielectric layer (2) and each sub-layer and the thickness of the amorphous In3SbTe2 phase change material layer (3) are set for each programmable thermal emission controller according to the thermal camouflage target color and the maximum spectral emissivity control range in the infrared bands of 3-5 microns and 8-14 microns; Step 2: According to the spectral emissivity target value, the area ratio of the grating structure crystal phase In3SbTe2 phase change interval (4) in each programmable thermal emission controller is adjusted, so that the spectral emissivity of each programmable thermal emission controller in the infrared bands of 3-5 microns and 8-14 microns approaches the spectral emissivity target value, thereby realizing the camouflage of the multi-band thermal camouflage device.

9. The application method of the multi-band compatible programmable thermal radiator based on indium antimony telluride according to claim 8, characterized in that: In step 1, the thermal camouflage target color is represented by coordinates in the CIE1931 xy colorimetric system: X is the stimulus value of red among the three primary colors, Y is the stimulus value of green among the three primary colors, and Z is the stimulus value of blue among the three primary colors; Where λ is the incident light wavelength of the square control monomer, S(λ) is the standard spectral radiation energy distribution of the D65 light source, and R(λ) is the spectral reflectivity of the thermal camouflage environment background or thermal camouflage object in the visible band; and are the standard matching functions for the three primary color stimulus values ​​respectively.

10. The application method of the multi-band compatible programmable thermal radiator based on indium antimony telluride according to claim 9, characterized in that: In step 2, the target value of spectral emissivity is obtained by inverting the normalized radiation intensity; the calculation method of normalized radiation intensity is: Where I norm is the normalized radiation intensity of each programmable thermal emission controller, I min It is the minimum radiation intensity of all programmable thermal emission controllers in the multi-band thermal camouflage device; I max is the maximum radiation intensity of all programmable thermal emission controllers in the multi-band thermal camouflage device; I is the radiation intensity of each programmable thermal emission controller: Where ε(λ) is the spectral emissivity of the programmable thermal emission controller, T is the temperature of the programmable thermal emission controller, and λ min is the initial wavelength of the incident light, λ max is the cut-off wavelength of the incident light, c1 is the first radiation constant, and its value is 3.7419×10 -16 W·m 2 ; c2 is the second radiation constant, with a value of 1.4388×10 -2 m.K.

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