Comment on "Catalytic Coherence"

Salil Bedkihal; Joan Vaccaro; Stephen Barnett

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arXiv · 1603.00003

Comment on "Catalytic Coherence"

Salil Bedkihal·Joan Vaccaro·Stephen Barnett

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Abstract

Aberg has claimed in a recent Letter," Phys. Rev. Lett. 113, 150402 (2014)", that the coherence of a reservoir can be used repeatedly to perform coherent operations without ever diminishing in power to do so. The claim has particular relevance for quantum thermodynamics because, as shown in "Phys. Rev. Lett. 113, 150402 (2014)", latent energy that is locked by coherence may be extractable without incurring any additional cost. We show here, however, that repeated use of the reservoir gives an overall coherent operation of diminished accuracy and is necessarily accompanied by an increased thermodynamic cost.

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Salil Bedkihal, Joan Vaccaro, Stephen Barnett. 2016-02-27. Comment on "Catalytic Coherence". https://arxiv.org/abs/1603.00003

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