Near-field radiative heat transfer between two parallel plates.

摘要

In theoretical studies supported by limited experimental results, it is stated that near-field radiative heat transfer exceeds blackbody radiation which has been defined as the limit of far-field radiative heat transfer. Its proof for two parallel plates requires novel experimental approach for precisely controlling nanoscale dimensions. In addition, a computational method is necessary to calculate near-field radiative heat transfer. In this study, the computational method is introduced and verification of the computational method is done by a proposed experimental approach. Near-field radiative heat transfer is compared with that of far-field using one half of a Wheatstone bridge circuit and an alignment procedure for controlling the distance between two parallel plates. To measure temperature effects of the near- and the far-field radiations, micro-sensors are designed and piezoelectric stages allowing sensitive relative positioning of two parallel plates are set up. Voltage read-outs acquired by a lock-in amplifier are converted to its temperature variation equivalent, and the comparison of near-field radiation with far-field radiation is presented for the two plate case. It is shown that near-field radiative heat transfer between two plates measured experimentally at nano-level has a good agreement with the results obtained from computations.