Tunable near-field thermal rectifiers by nanostructures

Abstract

The capability of manipulating heat flux at the nanoscale has important implications in thermal circuits and thermal management of electronics. In this work, by employing both the fluctuating surface current method and the Wiener-chaos expansion method, we demonstrate a tunable thermal rectification effect based on the near-field radiation for nanowire and nanocross structures. Due to the different decay behaviors of surface phonon polaritons and surface plasmon polaritons, the rectification can be bidirectionally controlled at various rates by tuning the separation between the nanostructures. This work provides new pathways for designing contactless smart thermal modulation devices.