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arXiv · 1911.12563

Floquet-state cooling

Onno R. Diermann·Martin Holthaus
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Abstract

We demonstrate that a periodically driven quantum system can adopt a quasistationary state which is effectively much colder than a thermal reservoir it is coupled to, in the sense that certain Floquet states of the driven-dissipative system can carry much higher population than the ground state of the corresponding undriven system in thermal equilibrium. This is made possible by a rich Fourier spectrum of the system's Floquet transition matrix elements, the components of which are addressed individually by a suitably peaked reservoir density of states. The effect is expected to be important for driven solid-state systems interacting with a phonon bath predominantly at well-defined frequencies.

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Onno R. Diermann, Martin Holthaus. 2019-11-28. Floquet-state cooling. https://doi.org/10.1038/s41598-019-53877-w

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