Thermoelectric cooling and thermal switching via the non-linear phonon Peltier effect

TL;DR

This paper explores a non-linear phonon Peltier effect in a quantum dot heat engine, revealing how electron-phonon interactions can generate and control phonon currents, enabling cooling and switching functionalities.

Contribution

It introduces the non-linear phonon Peltier effect in quantum dot systems and demonstrates charge-induced phonon generation, cooling, and switching mechanisms.

Findings

Phonon currents can be generated without thermal gradients due to electron-phonon interactions.

The heat engine can be cooled by reversing phonon currents via charge accumulation.

A charge-induced phonon switching mechanism is proposed.

Abstract

Investigating the non-linear transport regime in a quantum dot heat engine described by the Anderson-Holstein model, it is shown that a finite electron-phonon interaction leads to a charge induced phonon generation that stimulates a phonon current even in the absence of a thermal gradient. This gives rise to the non-linear phonon Peltier effect which shows a non-trivial dependence on varying the electron-phonon interaction. Utilizing the reversal of phonon currents via charge induced phonon accumulation, we demonstrate that the heat engine surprisingly can be cooled when coupled to a hot reservoir. In further exploring possibilities that can arise from this effect, we propose a charge-induced phonon switching mechanism.