Thermopower of a Luttinger-liquid-based Two-channel Charge Kondo Circuit: Nonperturbative Solution

Abstract

Recently, the influence of electron-electron interactions on the thermoelectric transport in a two-channel charge Kondo circuit has been studied in [Phys. Rev. B 105 (2022) L121405]. In this paper, we revisit the Luttinger-liquid-based model and discuss in details the limit when the spin mode is noninteracting (gs = 1) while the interaction in the charge sector is repulsive (gr 1). The thermoelectric transport coefficients are computed nonperturbatively with respect to the reflection amplitude at the quantum point contact. At low temperatures the thermopower shows the non-Fermi liquid behavior in the vicinity of the Coulomb peaks. We also demonstrate that repulsive interaction results in the enhancement of the thermoelectric power.