Emergence and control of heat current from strict zero thermal bias

TL;DR

This paper shows that nonlinear asymmetric systems can generate and control heat current without a thermal bias, revealing conditions necessary for energy transport at the nanoscale.

Contribution

It demonstrates that non-equilibrium, symmetry breaking, and nonlinearity enable heat current at zero thermal bias, providing new insights for nano-device energy control.

Findings

Heat current can be produced without thermal bias in nonlinear asymmetric systems.

Symmetry breaking alone can generate heat current when heat baths are correlated.

A broad parameter range allows control of heat flow in such systems.

Abstract

It is an ever-growing challenge to develop nano-devices for controlling energy transport. An open question is whether we can create and control heat current at {\it strict zero thermal bias}, and if yes, how to do it. In this paper, we demonstrate that a nonlinear asymmetric system, when pushed out of equilibrium, can produce heat current in the absence of a thermal bias. The emergence and control of heat current over a broad range of parameters are studied. Our results reveal the following three necessary conditions: non-equilibrium source, symmetry breaking, and nonlinearity. We also demonstrate that when heat baths are correlated, symmetry breaking is sufficient to generate heat current.