thermal magnification device is proposed by using effective thermal conductivity. Different fromtransformation optics method, the magnification design is realized analytically by enforcingequality of effective ther...thermal magnification device is proposed by using effective thermal conductivity. Different fromtransformation optics method, the magnification design is realized analytically by enforcingequality of effective thermal conductivity on the magnification device and the reference case inspecified domains. The validity of theoretical analysis is checked by numerical simulation results,which demonstrates the magnifying effects of the proposed design. The device only needsisotropic and homogeneous materials that are easy to obtain in nature. It is also shown that theobtained magnifying conditions are the same as those derived by separation of variables. But theproposed method proves more flexible for multilayered materials and simpler for non-sphericalobjects under non-uniform thermal fields. It can also be extended to other fields and applicationsgoverned by Laplace equation.展开更多
Infrared camouflage based on artificial thermal metasurfaces has recently attracted significant attention.By eliminating thermal radiation differences between the object and the background,it is possible to hide a giv...Infrared camouflage based on artificial thermal metasurfaces has recently attracted significant attention.By eliminating thermal radiation differences between the object and the background,it is possible to hide a given object from infrared detection.Infrared camouflage is an important element that increases the survivability of aircraft and missiles,by reducing target susceptibility to infrared guided threats.Herein,a simple and practicable design is theoretically presented based on a multilayer film for infrared stealth,with distinctive advantages of scalability,flexible fabrication,and structural simplicity.The multilayer medium consists of silicon substrate,carbon layer and zinc sulfide film,the optical properties of which are determined by transfer matrix method.By locally changing the thickness of the coating film,the spatial tunability and continuity in thermal emission are demonstrated.A continuous change of emissive power is further obtained and consequently implemented to achieve thermal camouflage functionality.In addition,other functionalities,like thermal illusion and thermal coding,are demonstrated by thickness-engineered multilayer films.展开更多
基金supported by the National Natural Science Foundation of China (11732002,11672089, 11325210, and 11421091)
文摘thermal magnification device is proposed by using effective thermal conductivity. Different fromtransformation optics method, the magnification design is realized analytically by enforcingequality of effective thermal conductivity on the magnification device and the reference case inspecified domains. The validity of theoretical analysis is checked by numerical simulation results,which demonstrates the magnifying effects of the proposed design. The device only needsisotropic and homogeneous materials that are easy to obtain in nature. It is also shown that theobtained magnifying conditions are the same as those derived by separation of variables. But theproposed method proves more flexible for multilayered materials and simpler for non-sphericalobjects under non-uniform thermal fields. It can also be extended to other fields and applicationsgoverned by Laplace equation.
基金supported by the EIPHI Graduate School(No.ANR-17-EURE-0002)the French Investissements d’Avenir program,project ISITEBFC(No.ANR-15-IDEX-03)+1 种基金the National Natural Science Foundation of China(Nos.12172102,11872160 and 11732002)the support of the Alexander von Humboldt Foundation through the Feodor Lynen Fellowship。
文摘Infrared camouflage based on artificial thermal metasurfaces has recently attracted significant attention.By eliminating thermal radiation differences between the object and the background,it is possible to hide a given object from infrared detection.Infrared camouflage is an important element that increases the survivability of aircraft and missiles,by reducing target susceptibility to infrared guided threats.Herein,a simple and practicable design is theoretically presented based on a multilayer film for infrared stealth,with distinctive advantages of scalability,flexible fabrication,and structural simplicity.The multilayer medium consists of silicon substrate,carbon layer and zinc sulfide film,the optical properties of which are determined by transfer matrix method.By locally changing the thickness of the coating film,the spatial tunability and continuity in thermal emission are demonstrated.A continuous change of emissive power is further obtained and consequently implemented to achieve thermal camouflage functionality.In addition,other functionalities,like thermal illusion and thermal coding,are demonstrated by thickness-engineered multilayer films.
