Modulating near-field thermal transfer through temporal drivings: a quantum many-body theory

TL;DR

This paper develops a quantum many-body theoretical framework using nonequilibrium Green's functions to analyze how periodic temporal drivings influence near-field thermal transfer, revealing effects like enhancement, suppression, and cooling.

Contribution

It introduces a novel quantum many-body approach for near-field heat transfer under periodic drivings, extending beyond traditional fluctuational electrodynamics to nonequilibrium states.

Findings

Demonstrates heat-transfer modulation via periodic drivings.

Shows potential for heat-transfer control including cooling effects.

Provides numerical analysis on Coulomb-coupled quantum dots.

Abstract

The traditional approach to studying near-field thermal transfer is based on fluctuational electrodynamics. However, this approach may not be suitable for nonequilibrium states due to dynamic drivings. In our work, we introduce a theoretical framework to describe the phenomenon of near-field heat transfer between two objects when subjected to periodic time modulations. We utilize the machinery of nonequilibrium Green's function to derive general expressions for the DC energy current in Floquet space. Furthermore, we also obtain the energy current under the condition of small driving amplitude. The external drivings create a nonequilibrium state, which gives rise to various effects such as heat-transfer enhancement, heat-transfer suppression, and cooling. To illustrate these phenomena, we conduct numerical calculations on a system of Coulomb-coupled quantum dots, and specifically investigate the scenario of periodically driving electronic reservoir. In our calculations, we employ the $G_0W_0$ approximation, which does not require self-consistent iteration and is suitable for weak Coulomb interaction. Our theoretical formalism can be applied to study near-field energy transfer between two metallic plates under periodic time modulations.