A near-field thermal radiation device with both thermal rectification and thermal stability

Abstract

The present application belongs to the technical field of semiconductor devices, and relates to a near-field thermal radiation device with thermal rectification and thermal stability, which is arranged in a vacuum cavity shell and comprises a negative thermal expansion substrate, an emitter, a thermal expansion substrate and a receiver. The negative thermal expansion substrate is arranged on a top wall in the vacuum cavity shell, the emitter is arranged on a side of the negative thermal expansion substrate away from the top wall of the vacuum cavity shell, the thermal expansion substrate is arranged on a bottom wall in the vacuum cavity shell, and the receiver is arranged on a side of the thermal expansion substrate away from the bottom wall of the vacuum cavity shell. The emitter and the receiver are used for near-field radiation heat transfer. By adjusting the temperature of the emitter and the receiver, the negative thermal expansion substrate and the thermal expansion substrate are expanded or contracted, the vacuum gap between the emitter and the receiver is changed, the heat flux of the near-field thermal radiation device is changed, and the near-field thermal radiation device realizes the functions of a thermal diode with thermal rectification and a thermal stabilizer with thermal stability.

Description

Technical Field

[0001] This invention relates to the field of semiconductor device technology, and in particular to a near-field thermal radiation device that combines thermal rectification and thermal stability. Background Technology

[0002] Near-field thermal radiation devices are devices that achieve efficient non-contact heat energy transport and control at the subwavelength scale based on the near-field thermal radiation effect. Their core lies in using evanescent wave coupling to break through the combined radiation limit and increase heat flux density. They are key technology carriers in the fields of micro-nano energy conversion, thermal management and sensing.

[0003] Existing near-field thermal radiation devices employ a binary architecture with separate basic functions. The transmitter serves as the energy output end on the heat source side, while the receiver serves as the heat flow receiving end. A fixed nano-gap layer between the transmitter and receiver acts as the core region for evanescent wave coupling. When the transmitter is heated to the target temperature by the heat source, a large number of evanescent waves are generated on its surface due to thermal excitation. When the distance between the transmitter and receiver is less than the characteristic wavelength of thermal radiation, the evanescent waves on both sides of the surface are coupled through the electromagnetic tunneling effect, realizing the transport of high-density heat flow from the transmitter to the receiver. The receiver then converts the absorbed thermal energy into electrical energy. Because existing near-field thermal radiation devices employ isotropic planar structures for both the transmitter and receiver, the evanescent waves excited on their surfaces propagate omnidirectionally. The nano-gap layer is a uniform dielectric layer without directional guidance, resulting in a random, diffuse heat flow during coupling and transmission. This means only coarse surface-to-surface transport can be achieved, not precise directional heat transport. Furthermore, the device's heat flux density is determined solely by the transmitter temperature, material properties, and fixed gap. When temperature changes cause material property drift, the device cannot adjust the evanescent wave coupling efficiency, leading to significant fluctuations in heat flux with temperature changes and preventing stable heat flux output. Additionally, since the transmitter and receiver only possess single functions such as thermal excitation or thermal absorption, the device cannot simultaneously achieve multiple functions of directional heat transport and stable heat flux, failing to meet the complex requirements of practical applications through integrated control.

[0004] In summary, existing near-field thermal radiation devices suffer from significant fluctuations in heat flux and performance degradation under temperature variations, making it impossible to simultaneously achieve multiple functions such as directional heat transport and stable heat flux, and thus failing to meet the integrated control requirements in practical applications. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problems of existing near-field thermal radiation devices having large fluctuations in heat flux and performance degradation under temperature change conditions, and being unable to simultaneously achieve multiple functions of directional heat transport and heat flux stability, thus failing to meet the integrated control requirements in practical applications.

[0006] To address the aforementioned technical problems, this invention provides a near-field thermal radiation device that combines thermal rectification and thermal stability. The near-field thermal radiation device is disposed within a vacuum cavity shell and includes: A negative thermal expansion substrate is disposed on the top wall inside the vacuum chamber shell; The transmitter is located on the side of the negative thermal expansion substrate away from the top wall of the vacuum chamber shell; A thermal expansion substrate is disposed on the bottom wall inside the vacuum chamber shell; The receiver is located on the side of the thermal expansion substrate away from the bottom wall of the vacuum chamber housing; The transmitter and receiver are used for near-field radiative heat transfer. By adjusting the temperature of the transmitter and receiver, the negative thermal expansion substrate and the thermal expansion substrate expand or contract, changing the vacuum gap between the transmitter and receiver, thereby changing the heat flux of the near-field thermal radiation device, enabling the near-field thermal radiation device to achieve the functions of thermal rectification thermal diode and thermal stability thermal stabilizer.

[0007] Preferably, the material of the negative thermal expansion substrate is a perovskite type, cristobalite type, zirconium phosphate type, titanium phosphate type, zeolite molecular sieve, metal-organic framework, alloy or intermetallic compound with a linear negative expansion rate. The material of the thermal expansion substrate is a silicone rubber, polyolefin elastomer, soft plastic, polyether elastomer, polyester elastomer, plasticized soft plastic, or high expansion elastomer with a linear positive expansion rate. The transmitter and receiver are made of polar semiconductors or inorganic polar materials.

[0008] Preferably, the negative thermal expansion substrate contracts when the temperature of the transmitter increases, and expands when the temperature of the transmitter decreases. When the temperature of the receiver increases, the thermal expansion substrate expands; when the temperature of the receiver decreases, the thermal expansion substrate contracts.

[0009] Preferably, the heat flux of the near-field thermal radiation device is proportional to the temperature difference between the transmitter and the receiver; The plasmonic mode coupling strength between the transmitter and receiver is inversely proportional to the temperature difference between the transmitter and receiver; The heat flux of a near-field thermal radiation device is inversely proportional to the square of the vacuum gap between the transmitter and receiver.

[0010] Preferably, the near-field thermal radiation device achieves the function of a thermal stabilizer for thermal stability by including: When the initial temperature of the transmitter is greater than the initial temperature of the receiver, the initial vacuum gap between the transmitter and receiver is: The initial heat flux of the near-field thermal radiation device is Near-field thermal radiation devices achieve the baseline state of the thermal stabilizer; When the temperature of the transmitter and / or receiver fluctuates, the temperature difference between them increases or decreases. Deformation of the negative thermal expansion substrate and / or the thermal expansion substrate causes the vacuum gap between the transmitter and receiver to increase or decrease. The change in heat flux caused by the change in vacuum gap offsets the change in heat flux caused by the change in temperature difference, thereby stabilizing the heat flux of the near-field thermal radiation device. Within the preset fluctuation range, it achieves the function of a thermal stabilizer that ensures thermal stability.

[0011] Preferably, when the temperature of the transmitter and / or receiver fluctuates, the temperature difference between the transmitter and receiver increases or decreases, and the deformation of the negative thermal expansion substrate and / or the thermal expansion substrate causes the vacuum gap between the transmitter and receiver to increase or decrease. The change in heat flux caused by the change in vacuum gap offsets the change in heat flux caused by the change in temperature difference, including: When the temperature of the transmitter increases while the temperature of the receiver remains constant, the temperature difference between the transmitter and receiver increases, which increases the heat flux of the near-field thermal radiation device. At the same time, the contraction of the negative thermal expansion substrate causes the vacuum gap between the transmitter and receiver to increase, which reduces the heat flux of the near-field thermal radiation device. When the temperature of the transmitter decreases and the temperature of the receiver remains constant, the temperature difference between the transmitter and the receiver decreases, which reduces the heat flux of the near-field thermal radiation device. At the same time, the expansion of the negative thermal expansion substrate causes the vacuum gap between the transmitter and the receiver to decrease, which increases the heat flux of the near-field thermal radiation device. When the temperature of the transmitter remains constant and the temperature of the receiver increases, the temperature difference between the transmitter and the receiver decreases, which reduces the heat flux of the near-field thermal radiation device. At the same time, the expansion of the thermal expansion substrate causes the vacuum gap between the transmitter and the receiver to decrease, which increases the heat flux of the near-field thermal radiation device. When the temperature of the transmitter remains constant and the temperature of the receiver decreases, the temperature difference between the transmitter and the receiver increases, which increases the heat flux of the near-field thermal radiation device. At the same time, the thermal expansion substrate contracts, which increases the vacuum gap between the transmitter and the receiver, which reduces the heat flux of the near-field thermal radiation device. When the temperature of the transmitter rises and the temperature of the receiver falls, the temperature difference between the transmitter and the receiver increases, which increases the heat flux of the near-field thermal radiation device. At the same time, the contraction of the negative thermal expansion substrate and the thermal expansion substrate causes the vacuum gap between the transmitter and the receiver to increase, which reduces the heat flux of the near-field thermal radiation device. When the temperature of the transmitter decreases and the temperature of the receiver increases, the temperature difference between the transmitter and the receiver decreases, which reduces the heat flux of the near-field thermal radiation device. At the same time, the expansion of the negative thermal expansion substrate and the thermal expansion substrate reduces the vacuum gap between the transmitter and the receiver, which increases the heat flux of the near-field thermal radiation device.

[0012] Preferably, if both the transmitter and receiver are silicon carbide, the initial temperature of the transmitter is 450K and the initial temperature of the receiver is 300K. The preset fluctuation range is [ , ], When the initial vacuum gap is When the thickness is 30nm, the thickness range of the negative thermal expansion substrate without deformation is (7.6μm, 8.5μm), the thickness range of the thermal expansion substrate without deformation is (0.11μm, 0.13μm), the temperature fluctuation range of the transmitter is greater than or equal to 50K, and the temperature fluctuation range of the receiver is greater than or equal to 40K. When the initial vacuum gap is When the thickness is 60nm, the thickness range of the negative thermal expansion substrate without deformation is (16.3μm, 19.7μm), the thickness range of the thermal expansion substrate without deformation is (0.26μm, 0.3μm), the temperature fluctuation range of the transmitter is greater than or equal to 50K, and the temperature fluctuation range of the receiver is greater than or equal to 40K.

[0013] Preferably, if both the transmitter and receiver are silicon carbide, the initial temperature of the transmitter is 450K and the initial temperature of the receiver is 300K. The preset fluctuation range is [ , ], When the initial vacuum gap is When the wavelength is 30nm, the maximum temperature fluctuation of the transmitter is greater than or equal to 70K, and the maximum temperature fluctuation of the receiver is [40K, 50K]. When the initial vacuum gap is At 60nm, the maximum temperature fluctuation of the transmitter is [100K, 110K], and the maximum temperature fluctuation of the receiver is [40K, 50K]. When the initial vacuum gap is At 80nm, the maximum temperature fluctuation of the transmitter is [90K, 100K], and the maximum temperature fluctuation of the receiver is [40K, 50K]. When the initial vacuum gap is When the wavelength is 100nm, the maximum temperature fluctuation of the transmitter is [50K, 70K], and the maximum temperature fluctuation of the receiver is [40K, 50K].

[0014] Preferably, the near-field thermal radiation device realizes the thermal diode function of thermal rectification by: When the initial temperature of the transmitter is greater than the initial temperature of the receiver, the initial vacuum gap between the transmitter and receiver is: The initial heat flux of the near-field thermal radiation device is Near-field thermal radiation devices achieve the reverse bias state of thermal diodes; When the transmitter's temperature drops to the receiver's initial temperature, and the receiver's temperature rises to the transmitter's initial temperature, the negative thermal expansion substrate expands, and the thermal expansion substrate contracts, causing the vacuum gap between the transmitter and receiver to decrease. The heat flux of the near-field thermal radiation device increased to Near-field thermal radiation devices achieve a forward bias state for thermal diodes, generating thermal rectification.

[0015] Preferably, if both the transmitter and receiver are silicon carbide, the initial temperature of the transmitter is 450K and the initial temperature of the receiver is 300K. The preset fluctuation range is [ , ], When the initial vacuum gap is When the thickness of the negative thermal expansion substrate is 30nm and the thickness ranges from (7.6μm, 8.5μm) to (0.11μm, 0.13μm), the efficiency of the thermal diode when the near-field thermal radiation device realizes the thermal rectification function is [90%, 95%]. When the initial vacuum gap is When the thickness of the negative thermal expansion substrate is 60nm and the thickness ranges from (16.3μm, 19.7μm) to (0.26μm, 0.3μm), the efficiency of the thermal diode when the near-field thermal radiation device realizes the thermal rectification function is 99%.

[0016] The near-field thermal radiation device provided in this application, which combines thermal rectification and thermal stability, is disposed within a vacuum chamber shell. It includes a negative thermal expansion substrate, an emitter, a thermal expansion substrate, and a receiver. The negative thermal expansion substrate is disposed on the top wall of the vacuum chamber shell, the emitter is disposed on the side of the negative thermal expansion substrate away from the top wall of the vacuum chamber shell, the thermal expansion substrate is disposed on the bottom wall of the vacuum chamber shell, and the receiver is disposed on the side of the thermal expansion substrate away from the bottom wall of the vacuum chamber shell. The emitter and receiver are used for near-field radiative heat transfer. By adjusting the temperatures of the emitter and receiver, the negative thermal expansion substrate and the thermal expansion substrate expand or contract, changing the vacuum gap between the emitter and receiver, thereby changing the heat flux of the near-field thermal radiation device. This allows the near-field thermal radiation device to achieve both the thermal rectification function of a thermal diode and the thermal stability function of a thermal stabilizer. Through the synergistic design of positive and negative expansion materials, the transmitter and receiver are respectively supported. When the ambient temperature changes, the negative thermal expansion substrate and the thermal expansion substrate expand or contract, thereby changing the vacuum gap between the transmitter and receiver. This alters the plasmon polariton coupling strength and the number of heat transfer channels between the transmitter and receiver. The change in heat flux caused by the change in vacuum gap offsets the change in heat flux caused by temperature difference, thus stabilizing the heat flux of the near-field thermal radiation device and achieving the function of a thermal stabilizer. Simultaneously, the asymmetric change in the vacuum gap triggered by the temperature difference between the transmitter and receiver forms a thermal diode effect. That is, when the transmitter temperature changes from being higher than the receiver temperature to being lower than the receiver temperature, the heat flux transport direction changes from receiver to transmitter to transmitter to receiver. At the same time, the heat flux increases due to the change in vacuum gap, achieving a thermal rectification function. The temperature self-response characteristics of the positive and negative thermal expansion materials transform the fixed vacuum gap into an active self-compensation mechanism. The change in vacuum gap solves the performance degradation and heat flux fluctuation caused by temperature changes. At the same time, the asymmetric gap change with temperature bias achieves the integrated integration of thermal rectification and thermal stability. Attached Figure Description

[0017] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein: Figure 1 A schematic diagram of a near-field thermal radiation device structure that combines thermal rectification and thermal stability, provided for this application; Figure 2 A schematic diagram illustrating the total energy transfer factor of the near-field thermal radiation device provided in this application as a function of angular frequency and normalized parallel wave vector; wherein, Figure 2 (a) in the diagram is a schematic diagram of the total energy transfer factor when the vacuum gap is 30 nm, the receiver temperature is 300 K, and the transmitter temperature is 400 K. Figure 2(b) in the diagram is a schematic of the total energy transfer factor when the vacuum gap is 30 nm, the receiver temperature is 300 K, and the transmitter temperature is 450 K. Figure 2 (c) in the diagram is a schematic of the total energy transfer factor when the vacuum gap is 30 nm, the receiver temperature is 300 K, and the transmitter temperature is 500 K. Figure 2 (d) in the diagram represents the total energy transfer factor when the transmitter temperature is 450K, the receiver temperature is 300K, and the vacuum gap is 30nm. Figure 2 (e) in the diagram represents the total energy transfer factor when the transmitter temperature is 450K, the receiver temperature is 300K, and the vacuum gap is 100nm. Figure 2 (f) in the figure is a schematic diagram of the total energy transfer factor when the temperature of the transmitter is 450K, the temperature of the receiver is 300K, and the vacuum gap is 300nm. Figure 3 This application provides a schematic diagram illustrating the working principle of the thermal stabilizer; wherein, Figure 3 (a) in the figure represents the baseline state of the thermal stabilizer. Figure 3 (b) in the diagram represents the first steady-flow state of the thermal stabilizer. Figure 3 (c) in the figure represents the second steady-flow state of the thermal stabilizer; Figure 4 A schematic diagram illustrating the operating range of the thermal stabilizer under different vacuum gaps provided in this application; wherein, Figure 4 (a) in the figure is a schematic diagram showing the relationship between the emitter temperature variation range of the thermal stabilizer under different vacuum gaps and the thickness variation of the negative thermal expansion substrate. Figure 4 (b) in the figure is a schematic diagram showing the relationship between the receiver temperature variation range of the thermal stabilizer under different vacuum gaps and the thickness variation of the negative thermal expansion substrate; Figure 5 A schematic diagram illustrating the heat flux stability of the near-field thermal radiation device provided in this application when the temperatures of the transmitter and receiver change simultaneously; wherein... Figure 5 (a) in the diagram is a schematic diagram of the heat flux stability of the near-field thermal radiation device when the thickness of both the negative thermal expansion substrate and the thermal expansion substrate is 0, and the temperatures of the transmitter and receiver change simultaneously. Figure 5 (b) is a schematic diagram of the heat flux stability of the near-field thermal radiation device when the thickness of the negative thermal expansion substrate is 8 μm and the thickness of the thermal expansion substrate is 0.1 μm. Figure 6 This application provides a schematic diagram illustrating the working principle of a thermal diode; wherein, Figure 6 (a) in the diagram represents the forward bias state of the thermal diode. Figure 6 (b) in the diagram represents the reverse bias state of the thermal diode; Figure 7A schematic diagram illustrating the rectification efficiency of thermal diodes under different vacuum gaps provided in this application; wherein, Figure 7 (a) in the figure is a schematic diagram showing the change in rectification efficiency of the thermal diode with respect to the negative thermal expansion substrate and the thickness of the thermal expansion substrate when the vacuum gap is 30 nm. Figure 7 (b) in the figure is a schematic diagram showing the change in the rectification efficiency of the thermal diode with respect to the negative thermal expansion substrate and the thickness of the thermal expansion substrate when the vacuum gap is 60 nm. Figure 7 (c) in the figure is a schematic diagram showing the change in the rectification efficiency of the thermal diode with the negative thermal expansion substrate and the thickness of the thermal expansion substrate when the vacuum gap is 80 nm. Figure 7 (d) in the figure is a schematic diagram showing the change of the rectification efficiency of the thermal diode with the negative thermal expansion substrate and the thickness of the thermal expansion substrate when the vacuum gap is 100nm. Explanation of reference numerals in the accompanying drawings: 1. Negative thermal expansion substrate; 2. Transmitter; 3. Thermal expansion substrate; 4. Receiver; 5. Vacuum gap. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0019] Please see Figure 1 , Figure 1 The diagram shows a near-field thermal radiation device that combines thermal rectification and thermal stability. The near-field thermal radiation device is housed in a vacuum chamber shell (not shown in the figure) and includes a negative thermal expansion substrate 1, an emitter 2, a thermal expansion substrate 3, and a receiver 4. The emitter 2 and the receiver 4 are separated by a vacuum gap 5.

[0020] The negative thermal expansion substrate 1 is disposed on the top wall inside the vacuum chamber shell.

[0021] The transmitter 2 is located on the side of the negative thermal expansion substrate 1 away from the top wall of the vacuum chamber shell.

[0022] The thermal expansion substrate 3 is disposed on the bottom wall inside the vacuum chamber shell.

[0023] The receiver 4 is located on the side of the thermal expansion substrate 3 away from the bottom wall of the vacuum chamber shell.

[0024] The transmitter 2 and receiver 4 are used for near-field radiative heat transfer. By adjusting the temperature of the transmitter 2 and receiver 4, the negative thermal expansion substrate 1 and thermal expansion substrate 3 expand or contract, changing the vacuum gap between the transmitter 2 and receiver 4, thereby changing the heat flux of the near-field thermal radiation device, enabling the near-field thermal radiation device to realize the thermal rectification thermal diode function and the thermal stability thermal stabilizer function.

[0025] It should be noted that since the negative thermal expansion substrate 1 and the thermal expansion substrate 3 are fixedly installed on the inner wall of the vacuum chamber shell, the deformation of the negative thermal expansion substrate 1 and the thermal expansion substrate 3 directly causes the vacuum gap between the transmitter 2 and the receiver 4 to change.

[0026] Furthermore, the material of the negative thermal expansion substrate 1 is a perovskite type, cristobalite type, zirconium phosphate type, titanium phosphate type, zeolite molecular sieve, metal-organic framework, alloy or intermetallic compound with a linear negative expansion rate.

[0027] For example, perovskite type ( It is mainly composed of halide perovskites, for example , , Titanium-based perovskite ,in, Rare earth elements; cristobalite type general formula is , As a metal, cristobalite is a typical silicate material with negative thermal expansion. It is low in cost, easy to prepare, and suitable for industrial ceramic composites, such as nepheline. Tridymite, cristobalite; zirconium phosphate type, such as α-zirconium phosphate. Titanium phosphate type, such as titanium phosphate Zirconium phosphate and titanium phosphate types have layered framework structures, suitable for compounding with polymers and metals to prepare low-expansion composite materials; zeolite molecular sieves such as type A, type X, and type Y zeolites; metal-organic frameworks such as... , Alloys or intermetallic compounds, such as manganese-based alloys like Mn-Cu, Mn-Ni, and Mn-Fe, and zirconium-based / hafnium-based intermetallic compounds, such as... , , Rare earth-transition metal compounds, such as , Titanium-based alloys, such as Ti-Nb and Ti-Ta.

[0028] The material of the thermal expansion substrate 3 is a silicone rubber, polyolefin elastomer, soft plastic, polyether elastomer, polyester elastomer, plasticized soft plastic or high expansion elastomer with a linear positive expansion rate.

[0029] For example, silicone rubber and PDMS are both silicon-based, have good compatibility, can be blended and modified, have a slightly higher coefficient of thermal expansion, and silicon-based materials have much better temperature resistance and weather resistance than ordinary organic rubbers, making them the most direct alternative / compound choice for PDMS. The coefficient of thermal expansion can be controlled by fillers, such as methyl vinyl silicone rubber, fluorosilicone rubber, and room temperature vulcanizing silicone rubber; polyolefin elastomers and soft plastics such as low-density polyethylene, polypropylene, polybutene-1, and thermoplastic polyolefins; polyether elastomers and polyester elastomers such as polyether-type thermoplastic polyurethane and styrene-based thermoplastic elastomers; plasticized soft plastics such as accelerated polyvinyl chloride, polyvinyl acetate, and polymethyl methacrylate; and high-expansion elastomers such as polyisoprene rubber, nitrile rubber, and polydimethicone elastomers.

[0030] The transmitter 2 and receiver 4 are made of polar semiconductors or inorganic polar materials; for example, silicon carbide, gallium nitride, aluminum nitride, indium nitride, zinc oxide, indium oxide, gallium oxide, zinc sulfide, zinc selenide, cadmium sulfide, cadmium selenide, aluminum gallium nitride, indium gallium nitride, aluminum indium gallium nitride, boron carbide, boron nitride, gallium arsenide, indium phosphide, indium arsenide, indium antimonide, germanium dioxide, barium titanate, lead zirconate titanate, silicon nitride, aluminum oxide, lead sulfide, lead selenide, lead telluride, indium tin oxide, and titanium carbide.

[0031] Specifically, calcium hexafluorostannate and polydimethylsiloxane have extremely high coefficients of thermal expansion, respectively. and Both materials possess the advantages of simple synthesis and low cost. Therefore, this application preferentially uses calcium hexafluorostannate and polydimethylsiloxane as the negative thermal expansion substrate 1 and thermal expansion substrate 3. Furthermore, silicon carbide possesses a temperature-dependent dielectric constant described by the Lorentz model, enabling it to support surface phonon polaritons (SPhPs), whose resonant frequency varies with temperature. This significantly enhances the near-field radiative heat flux between the transmitter 2 and receiver 4, making it temperature-dependent. Therefore, this application preferentially uses silicon carbide as the transmitter 2 and receiver 4. However, it is worth noting that although this temperature-dependent dielectric property is beneficial for stability and rectification performance, the near-field thermal radiation device provided in this application does not entirely rely on silicon carbide; any material with an operating frequency in the near-infrared to mid-infrared range can be used as a radiating element.

[0032] Specifically, for negative thermal expansion substrate 1 and thermal expansion substrate 3, assuming that the thermal deformation of the substrate is linear, it follows the formula: ,in, , This indicates a material with negative thermal expansion. Indicates thermally expanding materials, Indicates the thickness of the substrate due to thermal deformation. Indicates the linear expansion coefficient. Indicates the initial thickness of the substrate. Indicates the changed temperature. Indicates the initial temperature; for negative thermal expansion (NTE) materials, That is, when heated, the negative thermal expansion substrate 1 contracts, and when cooled, the negative thermal expansion substrate 1 expands. Conversely, for thermally expanding (TE) materials, That is, the thermal expansion substrate 3 expands when heated and contracts when cooled.

[0033] Specifically, when the temperature of transmitter 2 increases, negative thermal expansion substrate 1 contracts; when the temperature of transmitter 2 decreases, negative thermal expansion substrate 1 expands. When the temperature of receiver 4 increases, thermal expansion substrate 3 expands; when the temperature of receiver 4 decreases, thermal expansion substrate 3 contracts.

[0034] Furthermore, the change in the vacuum gap 5 between transmitter 2 and receiver 4 can be expressed as: ,in, This indicates the changed vacuum gap. This indicates the initial vacuum gap.

[0035] The heat flux of the near-field thermal radiation device is expressed as: ,in, This represents the heat flux of a near-field thermal radiation device. Indicates temperature as And the frequency is , The average energy of the Planck oscillator, ( () is the wave vector component parallel to the plate surface; total energy transfer factor The thermal flux is determined by the dielectric constant of the material, which includes contributions from both s-polarized and p-polarized propagating waves and evanescent waves. To simplify the theoretical model, this application only considers near-field radiative heat transfer (NFRHT) of a semi-infinite silicon carbide plate. It should be noted that a 1 μm thick silicon carbide plate can be approximated as semi-infinite. In the structure provided in this application, both the transmitter 2 and receiver 4 are made of silicon carbide and used as radiating elements, while the expansion substrate is only used to support and adjust the vacuum gap between the transmitter 2 and receiver 4. In the near-field region where the vacuum gap is much smaller than the thermal wavelength, the heat flux approximately follows... Scaling, this inverse square relationship is the basis for near-field thermal radiation devices to have the dual functions of thermal stabilizers and thermal diodes.

[0036] To explain the physical mechanism of near-field thermal radiation devices, this application also plots the total energy transfer factor. As angular frequency and normalized parallel wave vector functions, such as Figure 2 The diagram shows the total energy transfer factor of the near-field thermal radiation device provided in this application as a function of angular frequency and normalized parallel wave vector; where, Figure 2 (a) in the diagram is a schematic diagram of the total energy transfer factor when the vacuum gap is 30 nm, the receiver temperature is 300 K, and the transmitter temperature is 400 K. Figure 2 (b) in the diagram is a schematic of the total energy transfer factor when the vacuum gap is 30 nm, the receiver temperature is 300 K, and the transmitter temperature is 450 K. Figure 2 (c) in the diagram is a schematic of the total energy transfer factor when the vacuum gap is 30 nm, the receiver temperature is 300 K, and the transmitter temperature is 500 K. Figure 2 (d) in the diagram represents the total energy transfer factor when the transmitter temperature is 450K, the receiver temperature is 300K, and the vacuum gap is 30nm. Figure 2 (e) in the diagram represents the total energy transfer factor when the transmitter temperature is 450K, the receiver temperature is 300K, and the vacuum gap is 100nm. Figure 2 (f) in the figure is a schematic diagram of the total energy transfer factor when the temperature of the transmitter is 450K, the temperature of the receiver is 300K, and the vacuum gap is 300nm.

[0037] To simplify the analysis, Figure 2 Only two semi-infinite silicon carbide plates were studied. The frequencies of SPhPs emanating from the silicon carbide-vacuum interface at different temperatures are marked by solid white lines (300K), dashed lines (400K), dashed lines (450K), and dotted lines (500K), respectively. The frequencies of these SPhPs are determined by... It is confirmed that, among them, This represents the dielectric constant of silicon carbide. Indicate the real part, such as Figure 2 As shown, due to the temperature-induced redshift of these modes, the resonant frequencies of silicon carbide and SPhP decrease with increasing temperature.

[0038] exist Figure 2 In (a) to (c), the vacuum gap d = 30 nm and the temperature of receiver 4 are maintained. The temperature of transmitter 2 remains unchanged. The effect on near-field thermal radiation devices can be observed when near At that moment, the two white lines converge, and the maximum energy transfer factor moves towards higher... The linearity of the channel movement indicates that as the temperature difference between silicon carbide emitter 2 and receiver 4 decreases, the temperature-dependent surface plasmon polariton (SPhPs) modes they support are more strongly coupled, while as the temperature difference increases, they begin to decouple. This conclusion also applies to... constant, The changing situation.

[0039] exist Figure 2 In steps (d) to (f), maintain the temperature of the transmitter. , Regardless of changes in the vacuum gap d, the dashed and solid white lines remain in the same position. This means that the frequency of the SPhP on silicon carbide is independent of changes in the vacuum gap d. However, the maximum parallel wave vector corresponding to the transmission factor decreases inversely with the vacuum gap d, resulting in a decrease in heat flux with the square of the vacuum gap, as described above. Therefore, by combining the temperature-dependent dielectric constant characteristics of silicon carbide with the ability to adjust the gap distance of the expanding material, the near-field thermal radiation device provided in this application can achieve high-performance thermal stability and function as a thermal diode.

[0040] Specifically, the heat flux of the near-field thermal radiation device is directly proportional to the temperature difference between transmitter 2 and receiver 4. The plasmonic mode coupling strength between transmitter 2 and receiver 4 is inversely proportional to the temperature difference between them. The heat flux of the near-field thermal radiation device is inversely proportional to the square of the vacuum gap between transmitter 2 and receiver 4.

[0041] Furthermore, such as Figure 3 The diagram shown illustrates the working principle of the thermal stabilizer provided in this application. The thermal stabilizer function, which achieves thermal stability using near-field thermal radiation devices, includes: When the initial temperature of transmitter 2 greater than the initial temperature of receiver 4 At that time, the initial vacuum gap between transmitter 2 and receiver 4 is The initial heat flux of the near-field thermal radiation device is Near-field thermal radiation devices achieve the baseline state of the thermal stabilizer, such as Figure 3 As shown in (a) of the diagram.

[0042] When the temperature of transmitter 2 and / or receiver 4 fluctuates, the temperature difference between transmitter 2 and receiver 4 increases or decreases. The deformation of the negative thermal expansion substrate 1 and / or thermal expansion substrate 3 causes the vacuum gap between transmitter 2 and receiver 4 to increase or decrease. The change in heat flux caused by the change in vacuum gap offsets the change in heat flux caused by the change in temperature difference, thereby stabilizing the heat flux of the near-field thermal radiation device. Within the preset fluctuation range, it achieves the function of a thermal stabilizer that ensures thermal stability.

[0043] Specifically, when the temperature of transmitter 2 rises ( When the temperature of receiver 4 remains constant, the temperature difference between transmitter 2 and receiver 4 increases, resulting in an increase in the heat flux of the near-field thermal radiation device. Simultaneously, the contraction of the negative thermal expansion substrate 1 causes an increase in the vacuum gap between transmitter 2 and receiver 4, resulting in a decrease in the heat flux of the near-field thermal radiation device. Figure 3 As shown in (b) of the diagram.

[0044] When the temperature of transmitter 2 drops ( When the temperature of receiver 4 remains constant, the temperature difference between transmitter 2 and receiver 4 decreases, which reduces the heat flux of the near-field thermal radiation device. At the same time, the expansion of negative thermal expansion substrate 1 causes the vacuum gap between transmitter 2 and receiver 4 to decrease, which increases the heat flux of the near-field thermal radiation device.

[0045] When the temperature of transmitter 2 remains constant, the temperature of receiver 4 increases ( When the temperature difference between transmitter 2 and receiver 4 decreases, the heat flux of the near-field thermal radiation device decreases. Simultaneously, the expansion of the thermal expansion substrate 3 reduces the vacuum gap between transmitter 2 and receiver 4, thus increasing the heat flux of the near-field thermal radiation device. Figure 3 As shown in (c) in the figure.

[0046] When the temperature of transmitter 2 remains constant, the temperature of receiver 4 decreases. When the temperature difference between the transmitter 2 and the receiver 4 increases, the heat flux of the near-field thermal radiation device increases. At the same time, the thermal expansion substrate 3 contracts, causing the vacuum gap between the transmitter 2 and the receiver 4 to increase, which reduces the heat flux of the near-field thermal radiation device.

[0047] When the temperature of transmitter 2 increases and the temperature of receiver 4 decreases, the temperature difference between transmitter 2 and receiver 4 increases, which increases the heat flux of the near-field thermal radiation device. At the same time, the contraction of negative thermal expansion substrate 1 and thermal expansion substrate 3 causes the vacuum gap between transmitter 2 and receiver 4 to increase, which reduces the heat flux of the near-field thermal radiation device.

[0048] When the temperature of transmitter 2 decreases and the temperature of receiver 4 increases, the temperature difference between transmitter 2 and receiver 4 decreases, which reduces the heat flux of the near-field thermal radiation device. At the same time, the expansion of negative thermal expansion substrate 1 and thermal expansion substrate 3 causes the vacuum gap between transmitter 2 and receiver 4 to decrease, which increases the heat flux of the near-field thermal radiation device.

[0049] Specifically, when the ambient temperature fluctuates, the performance of non-radiative heat transfer devices becomes unstable. An adaptive thermal stabilizer can spontaneously maintain a constant heat flux despite temperature changes in transmitter 2 and receiver 4, thereby resisting environmental interference. In the near-field thermal radiation device designed in this application, the temperature of transmitter 2 is set to a high temperature. Set the receiver temperature to low. The following explains in detail the principle that the heat flux remains stable when the temperature of transmitter 2 changes. The same principle applies when the temperature of receiver 4 changes: When the temperature of transmitter 2 from Rise to At that time, two compensation mechanisms are activated. First, as the temperature of transmitter 2 moves away from the target area... First, the SPhPs mode coupling between transmitter 2 and receiver 4 weakens. Second, the negative thermal expansion substrate 1 contracts, driving transmitter 2 away from receiver 4 and reducing the number of high β channels available for heat transfer. These two effects work together to counteract the natural tendency of heat flux to increase with increasing temperature difference. Conversely, when the temperature of transmitter 2 decreases, the two mechanisms operate in opposite directions: the negative thermal expansion substrate 1 expands to reduce the vacuum gap, increasing the number of channels available for heat transfer, while the reduced temperature difference enhances mode coupling. Together, they compensate for the decrease in driving force and maintain a constant heat flux.

[0050] Furthermore, in order to quantitatively evaluate the performance of the thermal stabilizer, this application defines heat flux fluctuation rate. ,in, This represents the heat flux of a near-field thermal radiation device after a temperature change. Indicates the vacuum gap before temperature change. The heat flux of the near-field thermal radiation device is set. and The scope of work is defined as follows: , , and Corresponding to The lower and upper temperature boundaries, i.e., the intervals, are defined as follows: Any temperature within satisfies .

[0051] like Figure 4 The diagram shown illustrates the operating range of the thermal stabilizer under different vacuum gaps provided in this application; wherein, Figure 4 (a) in the figure is a schematic diagram showing the relationship between the emitter temperature variation range of the thermal stabilizer under different vacuum gaps and the thickness variation of the negative thermal expansion substrate. Figure 4 (b) in the figure is a schematic diagram showing the relationship between the receiver temperature variation range of the thermal stabilizer under different vacuum gaps and the thickness variation of the negative thermal expansion substrate.

[0052] exist Figure 4 In (a) of the middle, Keep constant, in The operating range (i.e., temperature fluctuation range) of transmitter 2 was calculated for different initial vacuum gaps (30nm, 60nm, 80nm, 100nm). For transmitter 2, the maximum achievable operating range exceeds 70K under all initial vacuum gaps, showing a trend of first increasing and then decreasing with increasing initial vacuum gap. Notably, when the initial vacuum gap is 60nm, the operating range of transmitter 2 reaches 108K. This means that transmitter 2 can withstand temperature fluctuations of up to 100K while maintaining an almost constant heat flux in the near-field thermal radiation device. This performance allows the near-field thermal radiation device to operate under extreme conditions.

[0053] exist Figure 4 In (b) of the middle, Keep constant, in The operating range (i.e., temperature fluctuation range) of receiver 4 was calculated for different initial vacuum gaps (30nm, 60nm, 80nm, 100nm). For receiver 4, even without the addition of expansion materials (such as... Figure 4 (b) Thermal expansion substrate thickness along the x-axis The receiver 4 has already demonstrated an operating range exceeding 15K; however, even with the addition of expanding material, the maximum operating range only reaches 40K~50K, slightly less than transmitter 2, but still sufficient for practical applications. Another significant difference from transmitter 2 is that the maximum operating range of receiver 4 increases with the increase of the initial vacuum gap, indicating that the maximum operating range of receiver 4 occurs at a larger initial vacuum gap than is studied in this example.

[0054] The above analysis shows that as the initial vacuum gap increases, the operating range curve gradually widens, indicating that near-field thermal radiation devices with larger initial vacuum gaps have a greater tolerance for temperature differences in the initial thickness of the expanding material.

[0055] This application also analyzes the stability of the heat flux of the near-field thermal radiation device when the temperatures of transmitter 2 and receiver 4 change simultaneously, such as... Figure 5 The diagram shown illustrates the thermal flux stability of the near-field thermal radiation device provided in this application when the temperatures of the transmitter and receiver change simultaneously; wherein, Figure 5 (a) in the diagram is a schematic diagram of the heat flux stability of the near-field thermal radiation device when the thickness of both the negative thermal expansion substrate and the thermal expansion substrate is 0, and the temperatures of the transmitter and receiver change simultaneously. Figure 5 (b) shows the thermal flux stability of the near-field thermal radiation device when the thickness of the negative thermal expansion substrate is 8 μm and the thickness of the thermal expansion substrate is 0.1 μm, with simultaneous temperature changes in both the transmitter and receiver. It should be noted that... Figure 5These are all schematic diagrams of heat flux stability when the initial vacuum gap is 30nm. The black dashed line, dotted line, and solid line represent fluctuation rates H of 1%, 3%, and 5%, respectively.

[0056] Figure 5 (a) shows the heat flux between transmitter 2 and receiver 4 as... and In this case, due to the absence of thermally expanding materials, near-field thermal radiation devices can only [expand / remain] within [the specified range]. The heat flux remains stable in the vicinity, indicating that the heat flux of the device exhibits small stability to temperature fluctuations in transmitter 2; for receiver 4, when At that time, receiver 4 can ensure heat flux stability within a fluctuation range of ±50K.

[0057] Figure 5 Figure (b) shows a schematic diagram of the heat flux stability of the near-field thermal radiation device when the thickness of the negative thermal expansion substrate 1 is 8 μm and the thickness of the thermal expansion substrate 3 is 0.1 μm, and the temperatures of the transmitter 2 and receiver 4 change simultaneously. By combining the inherent properties of silicon carbide with the distance control capability of the thermal expansion material, the heat flux stability of the device is greatly improved. At this time, the stable heat flux region is crescent-shaped, indicating that the device's tolerance to high temperature fluctuations is much higher than its tolerance to low temperature fluctuations. However, as long as the temperature difference is not extremely small (top left corner of the schematic diagram) or extremely large (bottom right corner of the schematic diagram), the heat flux of the device can remain constant within a 5% fluctuation range. Even in the extreme cases of extremely large or extremely small temperature differences, the fluctuation range is only about 30%, which is much lower than... Figure 5 60% of (a) in the middle.

[0058] Furthermore, based on the above analysis, it can be concluded that if both transmitter 2 and receiver 4 are silicon carbide, the initial temperature of transmitter 2 is 450K, and the initial temperature of receiver 4 is 300K. The preset fluctuation range is [ , ], When the initial vacuum gap is When the thickness is 30nm, the thickness range of the negative thermal expansion substrate 1 without deformation is (7.6μm, 8.5μm), the thickness range of the thermal expansion substrate 3 without deformation is (0.11μm, 0.13μm), the temperature fluctuation range of the transmitter 2 is greater than or equal to 50K, and the temperature fluctuation range of the receiver 4 is greater than or equal to 40K. When the initial vacuum gap is When the thickness is 60nm, the thickness range of the negative thermal expansion substrate 1 without deformation is (16.3μm, 19.7μm), the thickness range of the thermal expansion substrate 3 without deformation is (0.26μm, 0.3μm), the temperature fluctuation range of the transmitter 2 is greater than or equal to 50K, and the temperature fluctuation range of the receiver 4 is greater than or equal to 40K.

[0059] Furthermore, if both transmitter 2 and receiver 4 are silicon carbide, the initial temperature of transmitter 2 is 450K, and the initial temperature of receiver 4 is 300K. The preset fluctuation range is [ , ], When the initial vacuum gap is When the wavelength is 30nm, the maximum temperature fluctuation of transmitter 2 is greater than or equal to 70K, and the maximum temperature fluctuation of receiver 4 is [40K, 50K]. When the initial vacuum gap is When the wavelength is 60nm, the maximum temperature fluctuation of transmitter 2 is [100K, 110K], and the maximum temperature fluctuation of receiver 4 is [40K, 50K]. When the initial vacuum gap is When the wavelength is 80nm, the maximum temperature fluctuation of transmitter 2 is [90K, 100K], and the maximum temperature fluctuation of receiver 4 is [40K, 50K]. When the initial vacuum gap is When the temperature is 100nm, the maximum temperature fluctuation of transmitter 2 is [50K, 70K], and the maximum temperature fluctuation of receiver 4 is [40K, 50K].

[0060] Furthermore, such as Figure 6 The diagram shown illustrates the working principle of the thermal diode provided in this application. The thermal diode function of the near-field thermal radiation device for thermal rectification includes: When the initial temperature of transmitter 2 greater than the initial temperature of receiver 4 At that time, the initial vacuum gap between transmitter 2 and receiver 4 is ( The initial heat flux of the near-field thermal radiation device is ( Near-field thermal radiation devices achieve the reverse bias state of thermal diodes, such as... Figure 6 As shown in (a) of the diagram.

[0061] When the temperature of transmitter 2 drops to the initial temperature of receiver 4 ( The temperature of receiver 4 rises to the initial temperature of the transmitter. When the negative thermal expansion substrate 1 expands and the thermal expansion substrate 3 contracts, the vacuum gap between the transmitter 2 and the receiver 4 decreases. The heat flux of the near-field thermal radiation device increased to Near-field thermal radiation devices achieve a forward bias state for thermal diodes, generating thermal rectification, such as... Figure 6 As shown in (b) of the diagram.

[0062] Specifically, in near-field radiation thermal diodes, heat flux can only be transported in one direction. Similar to electronic diodes, thermal diodes play a crucial role in thermal calculations and thermal management, and have received considerable attention in recent years. In this application, receiver 4, under forward bias, has a temperature of 400K and a heat flux of... Under reverse bias, at a temperature of 300K, the heat flux is... The performance of a thermal diode is determined by its rectification efficiency. Representation, defined as .

[0063] Some near-field thermal diodes based on mode coupling or structural asymmetry achieve a rectification efficiency of about 90%. The near-field thermal radiation device provided in this application can achieve a near-perfect rectification efficiency of close to 100% when realizing the function of a thermal diode. In addition, since it shares the physical mechanism with the thermal stabilizer, it can also work as a thermal stabilizer and a thermal diode under the same set of parameters.

[0064] like Figure 7 The diagram shows the rectification efficiency of the thermal diodes under different vacuum gaps provided in this application; wherein, Figure 7 (a) in the figure is a schematic diagram showing the change in rectification efficiency of the thermal diode with respect to the negative thermal expansion substrate and the thickness of the thermal expansion substrate when the vacuum gap is 30 nm. Figure 7 (b) in the figure is a schematic diagram showing the change in the rectification efficiency of the thermal diode with respect to the negative thermal expansion substrate and the thickness of the thermal expansion substrate when the vacuum gap is 60 nm. Figure 7 (c) in the figure is a schematic diagram showing the change in the rectification efficiency of the thermal diode with the negative thermal expansion substrate and the thickness of the thermal expansion substrate when the vacuum gap is 80 nm. Figure 7 Figure (d) shows the rectifier efficiency of the thermal diode as a function of the negative thermal expansion substrate and the thickness of the thermal expansion substrate when the vacuum gap is 100 nm. The black area in the figure represents the situation where the thermal diode cannot work. This is because, under the forward bias state, the thermal expansion material expands excessively, causing the transmitter 2 and receiver 4 to contact when the separation is less than zero. The black dashed line, dotted line, and solid line are used to divide the areas where the rectifier efficiency exceeds 70%, which are 90% and 99%, respectively. It can be seen that by appropriately changing the initial thickness of the expansion material, the rectifier efficiency of the thermal diode can exceed 90%. On this basis, a thermal diode and a thermal stabilizer can be realized simultaneously over a wide operating range.

[0065] Specifically, in Figure 7 In the diagram, the red dotted line and shaded area define the parameter range of the thermal stabilizer. The operating range of transmitter 2 is greater than or equal to 50K, and the operating range of receiver 4 is greater than or equal to 40K. Clearly, as... Figure 7 As shown in (a), when the initial vacuum gap is 30 nm, the thickness of the negative thermal expansion substrate 1 without deformation ranges from (7.6 μm, 8.5 μm), and the thickness of the thermal expansion substrate 3 without deformation ranges from (0.11 μm, 0.13 μm), the temperature of the transmitter 2 fluctuates within the range of 50 K, and the temperature of the receiver 4 fluctuates within the range of 40 K. The heat flux of the near-field thermal radiation device can remain almost constant, and the rectification efficiency reaches 90%~95%. When the initial vacuum gap is 60 nm, the thickness of the negative thermal expansion substrate 1 without deformation ranges from (16.3 μm, 19.7 μm), and the thickness of the thermal expansion substrate 3 without deformation ranges from (0.26 μm, 0.3 μm), the temperature of the transmitter 2 fluctuates within the range of 50 K, and the temperature of the receiver 4 fluctuates within the range of 40 K. The heat flux of the near-field thermal radiation device can remain almost constant, and the rectification efficiency reaches 99%. However, as... Figure 7 As shown in (c) and (d), some or all of the red shaded areas fall within the range where the thermal diode cannot function properly, meaning that for devices with initial vacuum gaps of 80nm and 100nm, it is impossible to achieve both a high-efficiency thermal diode and a robust thermal stabilizer using the same set of parameters.

[0066] Furthermore, based on the above analysis, if both transmitter 2 and receiver 4 are silicon carbide, the initial temperature of transmitter 2 is 450K, and the initial temperature of receiver 4 is 300K. The preset fluctuation range is [ , ], When the initial vacuum gap is When the thickness of the negative thermal expansion substrate 1 is 30nm and the thickness ranges from (7.6μm, 8.5μm) to (0.11μm, 0.13μm), the efficiency of the thermal diode when the near-field thermal radiation device realizes the thermal rectification function is [90%, 95%]. When the initial vacuum gap is When the thickness of the negative thermal expansion substrate 1 is 60nm and the thickness ranges from (16.3μm, 19.7μm) to (0.26μm, 0.3μm) when the thickness of the thermal expansion substrate 3 is 60nm and the thickness ranges from (0.26μm, 0.3μm) when the thickness is 60nm and ...

[0067] This application is the first to design a passive control strategy for the synergistic configuration of positive and negative thermal expansion materials. It deeply integrates the thermal expansion characteristics of materials with the laws of near-field thermal radiation, and combines this with the auxiliary enhancement effect of temperature-induced surface phonon polaritons to achieve simultaneous integration of thermal rectification and thermal stabilization functions. This overturns the technical logic of traditional thermal management and provides a new principle support for multifunctional thermal control. Using the strong inverse correlation between near-field heat flux and the vacuum gap between the transmitter and receiver as the core control mechanism, it achieves dual-end thermal stability control. Under conditions of ±50K temperature fluctuations on both sides, the rate of change of heat flux can be controlled within 5%, and the temperature fluctuation range at the transmitter even exceeds 100K, achieving a level not addressed by existing technologies. In addition to its wide range of applications, it achieves an ultra-high thermal rectification efficiency of over 99% while maintaining thermal stability. Adopting a passive design, it requires no external power source or complex feedback control system, allowing it to adapt to the material selection needs of various application scenarios and achieve adaptive thermal management. It provides a novel technical solution for fields with stringent requirements for directional heat transport and stable heat flux, such as chip heat dissipation and aerospace. For example, it can adapt to the heat dissipation and thermal control needs of precision chips and high-density electronic devices, as well as the thermal management needs of various aerospace equipment in extreme environments, and the thermal safety and thermal regulation needs of various precision manufacturing processes and energy storage devices.

[0068] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A near-field thermal radiation device that combines thermal rectification and thermal stability, characterized in that, The near-field thermal radiation device is disposed within a vacuum cavity shell and includes: A negative thermal expansion substrate is disposed on the top wall inside the vacuum chamber shell; The transmitter is located on the side of the negative thermal expansion substrate away from the top wall of the vacuum chamber shell; A thermal expansion substrate is disposed on the bottom wall inside the vacuum chamber shell; The receiver is located on the side of the thermal expansion substrate away from the bottom wall of the vacuum chamber housing; The transmitter and receiver are used for near-field radiative heat transfer. By adjusting the temperature of the transmitter and receiver, the negative thermal expansion substrate and the thermal expansion substrate expand or contract, changing the vacuum gap between the transmitter and receiver, thereby changing the heat flux of the near-field thermal radiation device, enabling the near-field thermal radiation device to achieve the functions of thermal rectification thermal diode and thermal stability thermal stabilizer.

2. The near-field thermal radiation device with both thermal rectification and thermal stability according to claim 1, characterized in that, The materials of the negative thermal expansion substrate are perovskite type, cristobalite type, zirconium phosphate type, titanium phosphate type, zeolite molecular sieve, metal-organic framework, alloy or intermetallic compound with linear negative expansion rate; The material of the thermal expansion substrate is a silicone rubber, polyolefin elastomer, soft plastic, polyether elastomer, polyester elastomer, plasticized soft plastic, or high expansion elastomer with a linear positive expansion rate. The transmitter and receiver are made of polar semiconductors or inorganic polar materials.

3. The near-field thermal radiation device with both thermal rectification and thermal stability according to claim 1, characterized in that, When the temperature of the transmitter increases, the negative thermal expansion substrate contracts; when the temperature of the transmitter decreases, the negative thermal expansion substrate expands. When the temperature of the receiver increases, the thermal expansion substrate expands; when the temperature of the receiver decreases, the thermal expansion substrate contracts.

4. The near-field thermal radiation device with both thermal rectification and thermal stability according to claim 1, characterized in that, The heat flux of a near-field thermal radiation device is proportional to the temperature difference between the transmitter and the receiver. The plasmonic mode coupling strength between the transmitter and receiver is inversely proportional to the temperature difference between the transmitter and receiver; The heat flux of a near-field thermal radiation device is inversely proportional to the square of the vacuum gap between the transmitter and receiver.

5. The near-field thermal radiation device with both thermal rectification and thermal stability according to claim 4, characterized in that, The thermal stabilizer function of near-field thermal radiation devices to achieve thermal stability includes: When the initial temperature of the transmitter is greater than the initial temperature of the receiver, the initial vacuum gap between the transmitter and receiver is: The initial heat flux of the near-field thermal radiation device is Near-field thermal radiation devices achieve the baseline state of the thermal stabilizer; When the temperature of the transmitter and / or receiver fluctuates, the temperature difference between them increases or decreases. Deformation of the negative thermal expansion substrate and / or the thermal expansion substrate causes the vacuum gap between the transmitter and receiver to increase or decrease. The change in heat flux caused by the change in vacuum gap offsets the change in heat flux caused by the change in temperature difference, thereby stabilizing the heat flux of the near-field thermal radiation device. Within the preset fluctuation range, it achieves the function of a thermal stabilizer that ensures thermal stability.

6. The near-field thermal radiation device with both thermal rectification and thermal stability according to claim 5, characterized in that, When the temperature of the transmitter and / or receiver fluctuates, the temperature difference between the transmitter and receiver increases or decreases. Deformation of the negative thermal expansion substrate and / or the thermal expansion substrate causes the vacuum gap between the transmitter and receiver to increase or decrease. The change in heat flux caused by the change in vacuum gap offsets the change in heat flux caused by the change in temperature difference, including: When the temperature of the transmitter increases while the temperature of the receiver remains constant, the temperature difference between the transmitter and receiver increases, which increases the heat flux of the near-field thermal radiation device. At the same time, the contraction of the negative thermal expansion substrate causes the vacuum gap between the transmitter and receiver to increase, which reduces the heat flux of the near-field thermal radiation device. When the temperature of the transmitter decreases and the temperature of the receiver remains constant, the temperature difference between the transmitter and the receiver decreases, which reduces the heat flux of the near-field thermal radiation device. At the same time, the expansion of the negative thermal expansion substrate causes the vacuum gap between the transmitter and the receiver to decrease, which increases the heat flux of the near-field thermal radiation device. When the temperature of the transmitter remains constant and the temperature of the receiver increases, the temperature difference between the transmitter and the receiver decreases, which reduces the heat flux of the near-field thermal radiation device. At the same time, the expansion of the thermal expansion substrate causes the vacuum gap between the transmitter and the receiver to decrease, which increases the heat flux of the near-field thermal radiation device. When the temperature of the transmitter remains constant and the temperature of the receiver decreases, the temperature difference between the transmitter and the receiver increases, which increases the heat flux of the near-field thermal radiation device. At the same time, the thermal expansion substrate contracts, which increases the vacuum gap between the transmitter and the receiver, which reduces the heat flux of the near-field thermal radiation device. When the temperature of the transmitter rises and the temperature of the receiver falls, the temperature difference between the transmitter and the receiver increases, which increases the heat flux of the near-field thermal radiation device. At the same time, the contraction of the negative thermal expansion substrate and the thermal expansion substrate causes the vacuum gap between the transmitter and the receiver to increase, which reduces the heat flux of the near-field thermal radiation device. When the temperature of the transmitter decreases and the temperature of the receiver increases, the temperature difference between the transmitter and the receiver decreases, which reduces the heat flux of the near-field thermal radiation device. At the same time, the expansion of the negative thermal expansion substrate and the thermal expansion substrate reduces the vacuum gap between the transmitter and the receiver, which increases the heat flux of the near-field thermal radiation device.

7. The near-field thermal radiation device with both thermal rectification and thermal stability according to claim 6, characterized in that, If both the transmitter and receiver are made of silicon carbide, the initial temperature of the transmitter is 450K, and the initial temperature of the receiver is 300K. The preset fluctuation range is [ , ], When the initial vacuum gap is When the thickness is 30nm, the thickness range of the negative thermal expansion substrate without deformation is (7.6μm, 8.5μm), the thickness range of the thermal expansion substrate without deformation is (0.11μm, 0.13μm), the temperature fluctuation range of the transmitter is greater than or equal to 50K, and the temperature fluctuation range of the receiver is greater than or equal to 40K. When the initial vacuum gap is When the thickness is 60nm, the thickness range of the negative thermal expansion substrate without deformation is (16.3μm, 19.7μm), the thickness range of the thermal expansion substrate without deformation is (0.26μm, 0.3μm), the temperature fluctuation range of the transmitter is greater than or equal to 50K, and the temperature fluctuation range of the receiver is greater than or equal to 40K.

8. The near-field thermal radiation device with both thermal rectification and thermal stability according to claim 6, characterized in that, If both the transmitter and receiver are made of silicon carbide, the initial temperature of the transmitter is 450K, and the initial temperature of the receiver is 300K. The preset fluctuation range is [ , ], When the initial vacuum gap is When the wavelength is 30nm, the maximum temperature fluctuation of the transmitter is greater than or equal to 70K, and the maximum temperature fluctuation of the receiver is [40K, 50K]. When the initial vacuum gap is At 60nm, the maximum temperature fluctuation of the transmitter is [100K, 110K], and the maximum temperature fluctuation of the receiver is [40K, 50K]. When the initial vacuum gap is At 80nm, the maximum temperature fluctuation of the transmitter is [90K, 100K], and the maximum temperature fluctuation of the receiver is [40K, 50K]. When the initial vacuum gap is When the wavelength is 100nm, the maximum temperature fluctuation of the transmitter is [50K, 70K], and the maximum temperature fluctuation of the receiver is [40K, 50K].

9. The near-field thermal radiation device with both thermal rectification and thermal stability according to claim 4, characterized in that, Near-field thermal radiation devices that realize the thermal diode function of thermal rectification include: When the initial temperature of the transmitter is greater than the initial temperature of the receiver, the initial vacuum gap between the transmitter and receiver is: The initial heat flux of the near-field thermal radiation device is Near-field thermal radiation devices achieve the reverse bias state of thermal diodes; When the transmitter's temperature drops to the receiver's initial temperature, and the receiver's temperature rises to the transmitter's initial temperature, the negative thermal expansion substrate expands, and the thermal expansion substrate contracts, causing the vacuum gap between the transmitter and receiver to decrease. The heat flux of the near-field thermal radiation device increased to Near-field thermal radiation devices achieve a forward bias state for thermal diodes, generating thermal rectification.

10. The near-field thermal radiation device with both thermal rectification and thermal stability according to claim 8, characterized in that, If both the transmitter and receiver are made of silicon carbide, the initial temperature of the transmitter is 450K, and the initial temperature of the receiver is 300K. The preset fluctuation range is [ , ], When the initial vacuum gap is When the thickness of the negative thermal expansion substrate is 30nm and the thickness ranges from (7.6μm, 8.5μm) to (0.11μm, 0.13μm), the efficiency of the thermal diode when the near-field thermal radiation device realizes the thermal rectification function is [90%, 95%]. When the initial vacuum gap is When the thickness of the negative thermal expansion substrate is 60nm and the thickness ranges from (16.3μm, 19.7μm) to (0.26μm, 0.3μm), the efficiency of the thermal diode when the near-field thermal radiation device realizes the thermal rectification function is 99%.

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