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Quantum bath refrigeration towards absolute zero: challenging the unattainability principle
M Kolář1, D Gelbwaser-Klimovsky, R Alicki
1Department of Optics, Palacký University, Olomouc, Czech Republic.
Abstract:
A minimal model of a quantum refrigerator, 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 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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