Quantum refrigerator driven by current noise

TL;DR

This paper proposes a quantum refrigerator system using three flux-biased phase qubits driven by external current noise, achieving cooling and approaching Carnot efficiency.

Contribution

It introduces a self-contained quantum refrigerator scheme with effective temperature control via current noise, demonstrating near-Carnot efficiency.

Findings

The system can cool a target qubit effectively.

Efficiency approaches the Carnot limit.

Effective temperature differences drive the refrigeration process.

Abstract

We proposed a scheme to implement a self-contained quantum refrigerator system composed of three rf-SQUID qubits, or rather, flux-biased phase qubits. The three qubits play the roles of the target, the refrigerator and the heat engine respectively. We provide different effective temperatures for the three qubits, by imposing external current noises of different strengths. The differences of effective temperatures give rise to the flow of free energy and that drives the refrigerator system to cool down the target. We also show that the efficiency of the system approaches the Carnot efficiency.