# Description of quantum coherence in thermodynamic processes requires constraints beyond free energy

@article{Lostaglio2015DescriptionOQ, title={Description of quantum coherence in thermodynamic processes requires constraints beyond free energy}, author={Matteo Lostaglio and David Jennings and Terry Rudolph}, journal={Nature Communications}, year={2015}, volume={6} }

Recent studies have developed fundamental limitations on nanoscale thermodynamics, in terms of a set of independent free energy relations. Here we show that free energy relations cannot properly describe quantum coherence in thermodynamic processes. By casting time-asymmetry as a quantifiable, fundamental resource of a quantum state, we arrive at an additional, independent set of thermodynamic constraints that naturally extend the existing ones. These asymmetry relations reveal that the…

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