Quantum thermoelectric and heat transport in the overscreened Kondo regime: Exact conformal field theory results

TL;DR

This paper uses conformal field theory to analyze quantum charge, heat, and thermoelectric transport in the overscreened Kondo regime, revealing universal behaviors and critical exponents in non-Fermi liquid systems.

Contribution

It introduces an exact conformal field theory framework to study thermoelectric transport in multichannel Kondo systems, highlighting universal properties beyond Fermi liquid theory.

Findings

Universal low-temperature scaling laws for thermoelectric coefficients.

Dependence of thermoelectric properties on the number of orbital channels.

Universality of Lorenz ratio and power factor in non-Fermi liquid regimes.

Abstract

We develop a conformal-field theory approach for investigation of the quantum charge-, heat- and thermoelectric- transport through a quantum impurity fine tuned to a non-Fermi liquid regime. The non-Fermi-liquid operational mode is associated with the overscreened spin Kondo effect and controlled by the number of orbital channels. The universal low-temperature scaling and critical exponents for Seebeck and Peltier coefficients are investigated for the multichannel geometry. We derive and analyze the universal dependence of the thermoelectric coefficients on the number of orbital channels. We discuss the universality of Lorenz ratio and power factor beyond the Fermi Liquid paradigm. Different methods of verifying our findings based on the recent experiments are proposed.