Effects of Electronic Correlations on the Thermoelectric Power of the Cuprates

TL;DR

This paper explains anomalous thermoelectric power features in high-Tc cuprates through doping-dependent antiferromagnetic correlations using Hubbard model calculations.

Contribution

It introduces a theoretical approach combining the Hubbard model and fluctuation-exchange approximation to explain thermoelectric anomalies in cuprates.

Findings

Maximum of S explained by momentum-dependent scattering rate

Fermi surface shape influences sign change of S

Doping affects antiferromagnetic correlations and thermoelectric behavior

Abstract

We show that important anomalous features of the normal-state thermoelectric power S of high-Tc materials can be understood as being caused by doping dependent short-range antiferromagnetic correlations. The theory is based on the fluctuation-exchange approximation applied to Hubbard model in the framework of the Kubo formalism. Firstly, the characteristic maximum of S as function of temperature can be explained by the anomalous momentum dependence of the single-particle scattering rate. Secondly, we discuss the role of the actual Fermi surface shape for the occurrence of a sign change of S as a function of temperature and doping.