Thermoelectric Power of Insulators and Reconsideration of Kelvin's Relations at Low Temperatures

TL;DR

This paper revisits thermoelectric effects in insulators at low temperatures, proposing modifications to Kelvin's relations to align with the third law of thermodynamics, especially considering strong electron correlations.

Contribution

It introduces a revised theoretical framework for thermoelectric effects in insulators, extending Kelvin's relations to low-temperature regimes and strongly correlated systems.

Findings

Kelvin's relations need modification for insulators at low temperatures

Thermoelectric effects in Kondo insulators are theoretically analyzed

Strong correlations significantly influence thermoelectric behavior

Abstract

Thermoelectric effects in Kondo insulators are attracting interests because of the emerging possibility of developping better thermoelectric materials for a portable refrigerator without liquid coolant. In this article, the theory of thermoelectric effects are reinvestigated for insulators or semiconductors at low temperatures. It is found that the famous relations established by Lord Kelvin for metals in 1851 must be modified for insulators in order to be consistent with the third law of the thermodynamics. Effects of strong correlation are discussed.