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arXiv · 1806.10810

Cooperative many-body enhancement of quantum thermal machine power

Wolfgang Niedenzu·Gershon Kurizki
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Abstract

We study the impact of cooperative many-body effects on the operation of periodically-driven quantum thermal machines, particularly heat engines and refrigerators. In suitable geometries, $N$ two-level atoms can exchange energy with the driving field and the (hot and cold) thermal baths at a faster rate than a single atom due to their SU(2) symmetry that causes the atoms to behave as a collective spin-$N/2$ particle. This cooperative effect boosts the power output of heat engines compared to the power output of $N$ independent, incoherent, heat engines. In the refrigeration regime, similar cooling-power boost takes place.

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Wolfgang Niedenzu, Gershon Kurizki. 2018-11-02. Cooperative many-body enhancement of quantum thermal machine power. https://doi.org/10.1088/1367-2630%2Faaed55

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