Thermal Radiative Properties of a SiC Grating on a Photonic Crystal

Abstract

Spectral and directional control of thermal emission holds substantial importance in different kinds of applications, where heat transfer is predominantly by thermal radiation. Several configurations have previously been proposed, like using gratings, photonic crystals (PCs) and resonant cavities. In the present work, we investigate the thermal radiative properties of a microstructure consisting of a SiC grating on a photonic crystal. The emissivity of the microstructute is calculated with the rigorous coupled-wave analysis (RCWA) algorithm as a function of the angular frequency and the emission angle. The results reveal that thermal emission from the microstructure can exhibit very novel feature compared to those previously studied. Especially, significantly enhanced thermal emission can be achieved in a broad spectral band due to excitation of surface photon polaritons (SPhPs), PC modes, magnetic polaritons (MPs) and the coupling between them. We show that it is possible to flexibly control the thermal emission feature by adjusting the microstructure's dimensional parameters properly.

The influence of a Te-depleted surface on the thermoelectric transport properties of Bi2Te3nanowires

“…Additionally, surface boundary scattering in the NWs could contribute to the reduced thermal conductivity compared to bulk samples. However, it should be kept in mind that over 80% of the lattice thermal conductivity arises from phonons with a mean free path below 10 nm [33], which is significantly smaller than the characteristic sizes of the investigated NWs. Comparable reductions in thermal conductivity have been observed for electrodeposited Bi x Te 1-x NWs with diameters in the range of 55-100 nm, which has been attributed to surface boundary scattering [18] and grain boundary scattering [19].…”

Design and optimization of a SiC thermal emitter/absorber composed of periodic microstructures based on a non-linear method

“…[8][9][10][11][12] The advantage of using microstructures in the control of thermal radiation is that the confined electromagnetic resonant modes can be excited within the microstructures and thermal radiation from the microstructures can, by coupling with the resonant modes, exhibit novel spectral and directional selectivity feature. [13][14][15][16][17] Significant progress has been made in the design of thermal emitters/absorbers based on the excitation of electromagnetic resonant modes during the last decade. Depending on the purposes of different applications, many structures have been proposed to achieve promising feature of thermal emission, such as selective enhancement of emissivity in broad bandwidth and range of emission angle, [18][19][20][21] or in contrast, in ultra narrow bandwidth and range of emission angle.…”