Vacuum induced phonon transfer between two solid dielectric materials: Illustrating the case of Casimir force coupling

TL;DR

This paper investigates the potential for phonon-mediated heat transfer between two dielectric solids in vacuum, focusing on Casimir force coupling and its comparison with near-field thermal radiation.

Contribution

It introduces a general model for phonon transfer via Casimir force and analyzes its effectiveness relative to near-field thermal radiation.

Findings

Phonon transfer via Casimir force can surpass near-field thermal radiation under certain conditions.

The effectiveness of phonon transfer depends on material properties, gap distance, and temperature.

Casimir force coupling can induce significant heat transfer in vacuum between dielectrics.

Abstract

The natural transition from the radiative regime to the conductive regime of heat transfer between two identical isotropic dielectric solid materials, is questioned by investigating the possibility of induced phonon transfer in vacuum. We describe the process in a general way assuming a certain phonon coupling mechanism between the two identical solids, then we particularly illustrate the case of coupling through Casimir force. We analyze how this mechanism of heat transfer compares and competes with the near field thermal radiation using a local model of the dielectric function. We show that the former mechanism can be very effective and even overpass the latter mechanism depending on the nature of the solid dielectric materials, the distance gap between them as well as the operating temperature regime.