Coulomb-force-mediated heat transfer in the near field: Geometric effect

Abstract

It has been shown recently that the Coulomb part of electromagnetic interactions is more important than the transverse propagation waves for the near-field enhancement of heat transfer between metal objects at a distance of order nanometers. Here we present a theory focusing solely on the Coulomb potential between electrons hopping among tight-binding sites. When the relevant systems are reduced to very small geometry, for example, a single site, the enhancement is much higher compared to a collection of them packed within a distance of a few Å. We credit this to the screening effect. This result may be useful in designing metal-based metamaterials to enhance heat transfer much higher.

Generalized first-principles method to study near-field heat transfer mediated by Coulomb interaction

“…Using the nonequilibrium Green's functions (NEGF) method, the transmission coefficient is given by a Caroli formula [26] with screened Coulomb potential and spectrum function of polarizability. It is equivalent to the formula obtained from the Joule heating effect of charge fluctuations due to external electric fields [27,28] and agrees to the ppolarized evanescent modes without retardation effects [29,30].…”

Role of disorder in plasmon-assisted near-field heat transfer between two-dimensional metals

“…In this limit, heat transfer is dominated by the Coulomb interaction. Our analysis is based on the standard expression for the heat current per unit area [23,24,29,31,32],…”

Near field versus far field in radiative heat transfer between two-dimensional metals

“…The importance of magnetic coupling in the near-field heat transfer between well-conducting metals has been emphasized [11,12]. In the extreme near-field limit, heat transfer due to the electrostatic Coulomb interaction has also been studied [13][14][15][16][17][18][19].…”