Dynamic Tuning of Near‐Field Radiative Thermal Rectification

Abstract

Taking advantage of phase‐transition and reconfigurable metamaterials, dynamic control of nanoscale thermal modulation can be achieved through the near‐field radiative thermal rectification devices. Herein, an active‐tuning near‐field thermal rectifier using reconfigurable phase‐transition metamaterials is explored. The rectifier has two terminals separated by vacuum, working under a controllable operational temperature around the critical temperature of the phase‐transition material VO2. One of the terminals is a stretchable structure made of polydimethylsiloxane (PDMS) thin film and grating consisting of various types of phase‐transition material. The effects of various inclusion forms and all the related geometric parameters are well analyzed. The controllable nanoscale thermal modulation can be achieved and the ultrahigh rectification ratios of 23.7 and 19.8, the highest values ever predicted, can be obtained for two deformation scenarios, respectively. It will shed light on the dynamic tuning of small‐scale thermal transport and light manipulation.

Smart thermal management with near-field thermal radiation

“…These materials undergo a sudden and drastic change in their optical properties around their critical temperature. Among these materials, metal-insulator transition (MIT) materials have attracted significant attention to design radiative heat rectifiers [27][28][29][30][31][32][33][34]. A widely MIT material is vanadium dioxide (VO 2 ) which undergoes its phase transition at T c ≈ 340 K [35,36].…”

Effective Approximation Method for Nanogratings-induced Near-Field Radiative Heat Transfer

“…When the distance between two objects is comparable to or less than the thermal wavelength, the photon tunneling effect plays an essential role in the thermal radiative transfer, greatly enhancing the near-field radiative heat transfer (NFRHT) past the Planckian blackbody limit by several orders of magnitude [1][2][3][4][5][6]. Numerous theoretical studies on the NFRHT between various materials and nanostructures have been performed, such as transfer between two planar surfaces [1,7,8], two nanoparticles [8,9], two gratings [10][11][12][13][14], one sphere and plane [15], three bodies [16], and so on [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32]. Recently, many experimental reports have indicated that the NFRHT can exceed the blackbody limit for a plane-plane configuration [33][34][35][36][37][38].…”

“…Recently, many experimental reports have indicated that the NFRHT can exceed the blackbody limit for a plane-plane configuration [33][34][35][36][37][38]. Therefore, NFRHT is of great significance in a variety of engineering applications, such as energy management [17,[39][40][41][42], sensing, and micro/nano-electromechanical systems (M/NEMS) [43][44][45][46].…”

Radiative thermal rectification in many-body systems

“…This thermal rectification exploits the thermal dependence of optical properties of the materials in interaction [79][80][81][82], which naturally breaks the symmetry in the heat transport when the sign of the temperature gradient between the two solids is changed. In addition, a large asymmetry in the heat transport was reported in systems made with materials undergoing a phase change, such as metal-insulator transition materials [83][84][85][86][87][88][89][90][91][92][93][94][95][96] and normal metal-superconductor transition materials [97][98][99]. However, this strong rectification occurs only close to the critical temperature of these materials.…”