Heat transport through a two-level system embedded between two harmonic resonators

TL;DR

This paper studies heat transfer in a quantum system modeled by the Rabi model, revealing temperature-dependent conductance features and parameter sensitivities relevant for nanoscale thermal devices like heat transistors.

Contribution

It introduces a detailed analysis of heat transport in a two-level system coupled to harmonic oscillators using the NIBA approximation, highlighting unique temperature dependence and parameter sensitivities.

Findings

Thermal conductance exhibits a two-peak temperature dependence.

Heat transport is sensitive to system-bath coupling and hybridization strength.

Potential applications in superconducting circuit-based heat transistors.

Abstract

We investigate heat transport through an assembly consisting of a two-level system coupled between two harmonic oscillators, which is described by the quantum Rabi model, as a prototype of nanoscale heat devices using controllable multi-level systems. Using the noninteracting-blip approximation (NIBA), we find that the linear thermal conductance shows a characteristic temperature dependence with a two-peak structure. We also show that heat transport is sensitive to model parameters for weak system-bath coupling and strong hybridization between the two-level system and the harmonic oscillators. This property characteristic of the multi-level system is advantageous for applications such as a heat transistor, and can be examined in superconducting circuits.