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arXiv · 1210.4394

Ground state cooling is not possible given initial system-thermal bath factorization

Lian-Ao Wu·Dvira Segal·Paul Brumer
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Abstract

In this paper we prove that a fundamental constraint on the cooling dynamic implies that it is impossible to cool, via a unitary system-bath quantum evolution, a system that is embedded in a thermal environment down to its ground state, if the initial state is a factorized product of system and bath states. The latter is a crucial but artificial assumption often included in many descriptions of system-bath dynamics. The analogous conclusion holds for 'cooling' to any pure state of the system.

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Lian-Ao Wu, Dvira Segal, Paul Brumer. 2012-10-16. Ground state cooling is not possible given initial system-thermal bath factorization. https://doi.org/10.1038/srep01824

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