Near-field radiative heat transfer between closely spaced graphene and amorphous SiO$_2$

TL;DR

This paper develops a theory for near-field radiative heat transfer between graphene and amorphous SiO$_2$, highlighting the role of quantum fluctuations and drift velocity, with significant implications for nanoscale heat transfer.

Contribution

It introduces a model accounting for drifting carriers in graphene and quantum fluctuations, extending existing theories of near-field radiative heat transfer.

Findings

Quantum fluctuations significantly affect heat transfer at low temperatures and high electric fields.

Radiative heat transfer in suspended graphene exceeds blackbody limits by about three orders of magnitude.

Near-field transfer contributes notably to heat dissipation in graphene-based nanodevices.

Abstract

We study the near-field radiative energy transfer between graphene and an amorphous SiO$_2$ substrate. In comparison with the existing theories of near-field radiative heat transfer our theory takes into account that the free carriers in graphene are moving relative to the substrate with a drift velocity $v$. In this case the heat flux is determined by both thermal and quantum fluctuations. We find that quantum fluctuations give an important contribution to the radiative energy transfer for low temperatures and high electric field (large drift velocities). For nonsuspended graphene the near-field radiative energy transfer gives a significant contribution to the heat transfer, in addition to the contribution from phononic coupling. For suspended graphene (large separation) the corresponding radiative energy transfer coefficient at nanoscale gap is $\sim$ 3 orders of magnitude larger than radiative heat transfer coefficient of the blackbody radiation limit.