Thermo-Electric Power of Dirac Fermions in Graphene

TL;DR

This paper develops a theoretical model for the thermo-electric power in graphene with Dirac fermions, effectively explaining experimental low-temperature behaviors across various doping levels.

Contribution

It introduces a self-consistent Born approximation approach to calculate thermo-electric power, capturing coherence effects in low doping regimes.

Findings

Successfully explains experimental low-temperature thermo-electric power behavior

Highlights importance of coherence processes involving carriers in both bands

Provides a comprehensive theoretical framework for graphene thermoelectricity

Abstract

On the basis of self-consistent Born approximation for Dirac fermions under charged impurity scatterings in graphene, the theory for calculating the thermo-electric power is developed by using the heat current-current correlation function. The advantage of the present approach is its ability to effectively treat the low doping case where the coherence process involving carriers in both upper and lower bands becomes important. We show that the low temperature behavior of the thermo-electric power as function of the carrier concentration and the temperature observed by the experiments can be successfully explained by our calculation.