Saturation of radiative heat transfer due to many-body thermalization

TL;DR

This paper reveals that many-body thermalization can cause saturation of radiative heat transfer at nanoscale distances, even when materials exhibit local optical responses, impacting thermal management and measurement accuracy.

Contribution

It introduces a new saturation mechanism based on many-body thermalization effects, extending understanding beyond nonlocal optical responses.

Findings

Saturation occurs due to many-body thermalization, not just nonlocal optical effects.

Presence of a third body or external bath induces heat transfer saturation.

Thermalization impacts nanoscale thermal management and measurement interpretation.

Abstract

Radiative heat transfer between two bodies saturates at very short separation distances due to the nonlocal optical response of the materials. In this work, we show that the presence of radiative interactions with a third body or external bath can also induce a saturation of the heat transfer, even at separation distances for which the optical response of the materials is purely local. We demonstrate that this saturation mechanism is a direct consequence of a thermalization process resulting from many-body interactions in the system. This effect could have an important impact in the field of nanoscale thermal management of complex systems and in the interpretation of measured signals in thermal metrology at the nanoscale.