Three-qubit refrigerator with two-body interactions

TL;DR

This paper introduces a three-qubit quantum refrigerator using only two-body interactions, enabling heat extraction without external work and controllable heat fluxes, with potential for experimental realization.

Contribution

It demonstrates a three-qubit absorption refrigerator with only two-body interactions, simplifying implementation and expanding control over heat and work in quantum thermal machines.

Findings

Achieved heat extraction without external work using two-body interactions.

Modeled open-system dynamics with thermodynamically consistent master equations.

Showed control and amplification of heat flux via local field adjustments.

Abstract

We propose a three-qubit setup for the implementation of a variety of quantum thermal machines where all heat fluxes and work production can be controlled. An important configuration that can be designed is that of an absorption refrigerator, extracting heat from the coldest reservoir without the need of external work supply. Remarkably, we achieve this regime by using only two-body interactions instead of the widely employed three-body interactions. This configuration could be more easily realised in current experimental setups. We model the open-system dynamics with both a global and a local master equation thermodynamic-consistent approach. Finally, we show how this model can be employed as a heat valve, in which by varying the local field of one of the two qubits allows one to control and amplify the heat current between the other qubits.