Near-Field Radiative Heat Transfer Between Two SiC Plates With/Without Coated Metal Films.

Near-field radiation is important in many nanotechnological applications, such as thermophotovoltaic system. In this paper, we employ the Rytov theory to calculate the near-field heat transfer between two silicon carbide (SiC) plates at finite vacuum gaps. The result shows that the total energy transfer rate increases with decreasing distance, and a maximum energy transfer rate can be found with respect to frequency. We then analyze the near-field thermal radiation of an aluminum-coated SiC plane in vacuum. The relation among film thickness, gap distance and energy density is given. It shows that the contribution of transverse electric (TE) mode to the energy density vanishes when the film thickness is nearly zero; and the contribution of transverse magnetic (TM) mode increases, but remains finite that can be illustrated by simple Drude model. The spectral density of p state of the thermally stimulated field in the vacuum-Al-SiC structure with fixed film thickness would have more resonance and large value can be obtained when increasing the distance; while the spectral density of p state in the thermally stimulated field in the structure with fixed distance has no apparent difference when varying the film thicknesses. This investigation can be extended for many other basic researches in near-field radiation.