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arXiv · 2502.14447

Thermal conductance at the superradiant phase transition in the quantum Rabi model

Tsuyoshi Yamamoto·Yasuhiro Tokura
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Abstract

The quantum Rabi model exhibits a superradiant phase transition when the coupling becomes strong, even though it involves only two components: a two-level atom and a single bosonic mode. This phase transition is referred to as a finite-component quantum phase transition, in contrast to conventional phase transitions in many-body systems. In this Letter, we investigate heat transport across an atom embedded in bosonic modes, modeled by the quantum Rabi model, between two thermal baths. We found a manifestation of the superradiant phase transition in the thermal conductance, which represents the linear response to a temperature bias. Our Letter can be helpful for the development of quantum heat devices utilizing controllable finite-component quantum phase transitions.

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Tsuyoshi Yamamoto, Yasuhiro Tokura. 2025-02-20. Thermal conductance at the superradiant phase transition in the quantum Rabi model. https://doi.org/10.1103/physrevb.111.l201409

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