Thermophonon flux in double-cavity optomechanics

Abstract

We propose theoretically an optomechanical system with double cavities to explore the thermophonon transport from the thermal bath of the mechanical oscillator to the coupled system. We find that the direction and magnitude of thermophonon flux in the system can be controlled flexibly by coupling an active cavity with gain to the driven cavity. In particular, the injected squeezing vacuum can reverse the nonequilibrium characteristics of the system and change the thermophonon flux from positive to negative. We also investigate in detail the influence of the driving power and the photon tunneling strength on the flux, which can widen the energy transfer channel of the system. The results obtained here have a potential application in the thermal noise energy harvesting and rectification by the optomechanical setup.