Thermoelectric effects in a double quantum dot system weakly coupled to ferromagnetic leads

TL;DR

This paper investigates thermoelectric effects in a double quantum dot system coupled to ferromagnetic leads, analyzing how polarization, temperature, and tunneling influence thermoelectric efficiency and conductance.

Contribution

It provides formal expressions for thermoelectric properties and explores how lead polarization, temperature, and tunneling affect the figure of merit in such systems.

Findings

Thermopower is unaffected by lead polarization.

Increased polarization reduces the figure of merit.

Higher interdot tunneling decreases the figure of merit.

Abstract

Thermoelectric effects through a serial double quantum dot system weakly coupled to ferromagnetic leads are analyzed. Formal expressions of electrical conductance, thermal conductance, and thermal coefficient are obtained by means of Hubbard operators. The results show that although the thermopower is independent of the polarization of the leads, the figure of merit is reduced by an increase of polarization. The influences of temperature and interdot tunneling on the figure of merit are also investigated, and it is observed that increase of the interdot tunneling strength results in reduction of the figure of merit. The effect of temperature on the thermal conductance is also analyzed.