Resonant scattering induced thermopower in one-dimensional disordered systems

TL;DR

This paper investigates how resonant scattering in one-dimensional disordered systems influences thermopower, revealing that localization and sharp conductance resonances can enhance thermoelectric efficiency.

Contribution

It introduces an analytical framework for understanding thermoelectric properties in disordered systems with resonant scatterers, combining localization effects with conductance resonances.

Findings

Resonant scatterers create sharp conductance features affecting thermopower.

Localization degree can be used to improve thermoelectric performance.

Analytical results agree qualitatively with numerical simulations.

Abstract

This study analyzes thermoelectric properties of a one-dimensional random conductor which shows localization effects and simultaneously includes resonant scatterers yielding sharp conductance resonances. These sharp features give rise to a distinct behavior of the Seebeck coefficient in finite systems and incorporate the degree of localization as a means to enhance thermoelectric performance, in principle. The model for non-interacting electrons is discussed within the Landauer-B\"uttiker formalism such that analytical treatment is possible for a wide range of properties, if a special averaging scheme is applied. The approximations in the averaging procedure are tested with numerical evaluations showing good qualitative agreement, with some limited quantitative disagreement. The validity of low-temperature Mott's formula is determined and a good approximation is developed for the intermediate temperature range. In both regimes the intricate interplay between Anderson localization due to disorder and conductance resonances of the disorder potential is analyzed.