Kapitza-like modulation of near-field radiative heat transfer

TL;DR

This paper introduces a Kapitza-like mechanism for near-field radiative heat transfer, demonstrating how rapid modulation of system parameters can significantly alter thermal flux and stability in nanoscale systems.

Contribution

The authors develop a theoretical framework for a Kapitza-like modulation effect in near-field radiative heat transfer, including analytical laws and experimental predictions.

Findings

Modulation induces measurable temperature shifts and modifies thermal conductances.

The effect can stabilize or destabilize thermal steady states.

Predicted temperature shifts are detectable with existing experimental setups.

Abstract

We introduce a Kapitza-like mechanism for the near-field radiative heat transfer and show that fast modulation of any parameter controlling the flux, such as the vacuum gap or a material response, produces a quadratic, time-averaged correction in the slow thermal dynamics. This correction splits into a frequency-independent static term and a low-pass dynamical term, yielding sizable modulation-induced temperature shifts and modified effective thermal conductances that can stabilize or destabilize the steady state. Applying the theory to gap modulation between SiC slabs, we derive analytical scaling laws and predict temperature shifts that are fully measurable with existing experimental platforms, requiring only readily accessible low modulation frequencies of order $\Omega \approx 10^4~\mathrm{rad/s}$. Our results establish a thermal analogue of the Kapitza mechanism and provide a general route for controlling radiative heat flow in micro- and nanoscale platforms.