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arXiv · 1702.00226

Capacitor physics in ultra-near-field heat transfer

Jian-Sheng Wang·Jiebin Peng
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Abstract

Using the nonequilibrium Green's function (NEGF) formalism, we propose a microscopic theory for near-field heat transfer between charged metal plates focusing on the Coulomb interactions. Tight-binding models for the electrons are coupled to the electromagnetic field continuum through a scalar potential. Our approach differs from the established ones based on Rytov fluctuational electrodynamics, which deals with the transverse radiative field and vector potential. For a two quantum-dot model a new length scale emerges below which the heat current exhibits great enhancement. This length scale is related to the physics of parallel plate capacitors. At long distances $d$, the energy flux decreases as $1/d^2$.

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Jian-Sheng Wang, Jiebin Peng. 2017-02-01. Capacitor physics in ultra-near-field heat transfer. https://doi.org/10.1209/0295-5075/118/24001

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