Non-linear thermoelectrics of molecular junctions with vibrational coupling

TL;DR

This paper investigates the non-linear thermoelectric behavior of a molecular junction modeled by a dissipative Anderson-Holstein system, highlighting how vibrational modes influence heat and charge transport, efficiency, and optimal operation.

Contribution

It introduces a detailed analysis of vibrational effects on thermoelectric performance in molecular junctions using a comprehensive model, revealing qualitative changes in optimal conditions.

Findings

Vibrational modes significantly alter thermoelectric efficiency.

Optimal operating conditions are qualitatively affected by vibrational coupling.

The study provides insights into designing molecular junctions for thermoelectric applications.

Abstract

We present a detailed study of the non-linear thermoelectric properties of a molecular junction, represented by a dissipative Anderson-Holstein model. A single orbital level with strong Coulomb interaction is coupled to a localized vibrational mode and we account for both electron and phonon exchange with both electrodes, investigating how these contribute to the heat and charge transport. We calculate the efficiency and power output of the device operated as a heat to electric power converter and identify the optimal operating conditions, which are found to be qualitatively changed by the presence of the vibrational mode. Based on this study of a generic model system, we discuss the desirable properties of molecular junctions for thermoelectric applications.