Heat transfer in the spin-boson model: A comparative study in the incoherent tunneling regime

TL;DR

This paper analyzes heat transfer in the non-equilibrium spin-boson model with Ohmic dissipation, deriving a thermal conductance formula in the incoherent tunneling regime and validating it against exact relations.

Contribution

It introduces a rate equation-based formula for thermal conductance in the spin-boson model, valid for temperatures above the Kondo temperature, and compares weak and strong coupling regimes.

Findings

Derived analytical expression for thermal conductance

Validated formula against exact relations

Explored far-from-equilibrium behavior

Abstract

We study the transfer of heat in the non-equilibrium spin-boson model with an Ohmic dissipation. In the non-adiabatic limit we derive a formula for the thermal conductance based on a rate equation formalism at the level of the non-interacting blip approximation, valid for temperatures $T>T_K$, with $T_K$ as the Kondo temperature. We evaluate this expression analytically assuming either weak or strong couplings, and demonstrate that our results agree with exact relations. Far-from-equilibrium situations are further examined, showing a close correspondence to the linear response limit.