Thermoelectric transport through a quantum nanoelectromechanical system and its backaction

TL;DR

This paper investigates how a quantum nanomechanical resonator influences thermoelectric transport in a single-electron transistor, revealing control over current direction, thermoelectric efficiency, and backaction effects.

Contribution

It provides a detailed analysis of the impact of SET-NR coupling on thermoelectric properties and backaction, highlighting new ways to control and optimize NEMS performance.

Findings

SET-NR coupling can switch thermoelectric current direction

Small SET-NR coupling significantly reduces ZT figure of merit

Backaction can be minimized by tuning gate voltage

Abstract

We present a comprehensive study of thermoelectric transport properties of a quantum nanoelectromechanical system (NEMS) described by a single-electron-transistor (SET) coupled to a quantum nanomechanical resonator (NR). The effects of a quantum NR on the electronic current are investigated with special emphasis on how the SET-NR coupling strength plays a role in such a NEMS. We find that the SET-NR coupling is not only able to suppress or enhance the thermoelectric current but can also switch its direction. The effect of the NR on the thermoelectric coefficients of the SET are studied and we find that even a small SET-NR coupling could dramatically suppress the figure of merits ZT . Lastly, we investigate the backaction of electronic current on the NR and possible routes of heating or cooling the NR are discussed. We find that by appropriately tuning the gate voltage the backaction can be eliminated, which could find possible applications to enhance the sensitivity of detection devices.