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arXiv · 1208.1015

Quantum bath refrigeration towards absolute zero: unattainability principle challenged

Michal Kolář·David Gelbwaser-Klimovsky·Robert Alicki·Gershon Kurizki
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Abstract

A minimal model of a quantum refrigerator (QR), i.e. a periodically phase-flipped two-level system permanently coupled to a finite-capacity bath (cold bath) and an infinite heat dump (hot bath), is introduced and used to investigate the cooling of the cold bath towards the absolute zero (T=0). Remarkably, the temperature scaling of the cold-bath cooling rate reveals that it does not vanish as T->0 for certain realistic quantized baths, e.g. phonons in strongly disordered media (fractons) or quantized spin-waves in ferromagnets (magnons). This result challenges Nernst's third-law formulation known as the unattainability principle.

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Michal Kolář, David Gelbwaser-Klimovsky, Robert Alicki, Gershon Kurizki. 2012-08-05. Quantum bath refrigeration towards absolute zero: unattainability principle challenged. https://doi.org/10.1103/physrevlett.109.090601

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