Three-terminal thermoelectric transport through a molecular junction

TL;DR

This paper investigates how inelastic electron-vibration interactions in a molecular junction enable thermoelectric conversion, especially when the molecule is coupled to a thermal bath at a different temperature, leading to potential efficiency improvements.

Contribution

It introduces a theoretical framework for thermoelectric transport in molecular junctions considering inelastic processes and thermal bath effects, highlighting new mechanisms for heat-to-electricity conversion.

Findings

Heat current can be converted into electric current via inelastic processes.

Strong coupling to a thermal bath influences thermoelectric coefficients.

Expressions for transport coefficients are derived and potential enhancement scenarios outlined.

Abstract

The thermoelectric transport through a molecular bridge is discussed, with an emphasis on the effects of inelastic processes of the transport electrons caused by the coupling to the vibrational modes of the molecule. In particular it is found that when the molecule is strongly coupled to a thermal bath of its own, which may be at a temperature different from those of the electronic reservoirs, a heat current between the molecule and the electrons can be converted into electric current. Expressions for the transport coefficients governing this conversion and similar ones are derived, and a possible scenario for increasing their magnitudes is outlined.