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arXiv · 2003.06437

Work as an external quantum observable and an operational quantum work fluctuation theorem

Konstantin Beyer·Kimmo Luoma·Walter T. Strunz
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Abstract

We propose a definition of externally measurable quantum work in driven systems. Work is given as a quantum observable on a control device which is forcing the system and can be determined without knowledge of the system Hamiltonian $H_\mathcal{S}$. We argue that quantum work fluctuation theorems which rely on the knowledge of $H_\mathcal{S}$ are of little practical relevance, contrary to their classical counterparts. Using our framework, we derive a fluctuation theorem which is operationally accessible and could in principle be implemented in experiments to determine bounds on free energy differences of unknown systems.

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Konstantin Beyer, Kimmo Luoma, Walter T. Strunz. 2020-03-13. Work as an external quantum observable and an operational quantum work fluctuation theorem. https://doi.org/10.1103/physrevresearch.2.033508

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