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arXiv · 2210.07844

Performance boost of a collective qutrit refrigerator

Dmytro Kolisnyk·Gernot Schaller
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Abstract

A single qutrit with transitions selectively driven by weakly-coupled reservoirs can implement one of the world's smallest refrigerators. We analyze the performance of $N$ such fridges that are collectively coupled to the reservoirs. We observe a quantum boost, manifest in a quadratic scaling of the steady-state cooling current with $N$. As $N$ grows further, the scaling reduces to linear, since the transitions responsible for the quantum boost become energetically unfavorable. Fine-tuned inter-qutrit interactions may be used to maintain the quantum boost for all $N$ and also for not-perfectly collective scenarios.

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Dmytro Kolisnyk, Gernot Schaller. 2022-10-14. Performance boost of a collective qutrit refrigerator. https://doi.org/10.1103/physrevapplied.19.034023

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