No-Go Theorem for the Characterization of Work Fluctuations in Coherent Quantum Systems

Martí Perarnau-Llobet, Elisa Bäumer, Karen V. Hovhannisyan, Marcus Huber, Antonio Acin

Research output: Contribution to journalArticleResearchpeer-review

52 Citations (Scopus)

Abstract

© 2017 American Physical Society. An open question of fundamental importance in thermodynamics is how to describe the fluctuations of work for quantum coherent processes. In the standard approach, based on a projective energy measurement both at the beginning and at the end of the process, the first measurement destroys any initial coherence in the energy basis. Here we seek extensions of this approach which can possibly account for initially coherent states. We consider all measurement schemes to estimate work and require that (i) the difference of average energy corresponds to average work for closed quantum systems and that (ii) the work statistics agree with the standard two-measurement scheme for states with no coherence in the energy basis. We first show that such a scheme cannot exist. Next, we consider the possibility of performing collective measurements on several copies of the state and prove that it is still impossible to simultaneously satisfy requirements (i) and (ii). Nevertheless, improvements do appear, and in particular, we develop a measurement scheme that acts simultaneously on two copies of the state and allows us to describe a whole class of coherent transformations.
Original languageEnglish
Article number070601
JournalPhysical Review Letters
Volume118
Issue number7
DOIs
Publication statusPublished - 14 Feb 2017

Fingerprint Dive into the research topics of 'No-Go Theorem for the Characterization of Work Fluctuations in Coherent Quantum Systems'. Together they form a unique fingerprint.

  • Cite this

    Perarnau-Llobet, M., Bäumer, E., Hovhannisyan, K. V., Huber, M., & Acin, A. (2017). No-Go Theorem for the Characterization of Work Fluctuations in Coherent Quantum Systems. Physical Review Letters, 118(7), [070601]. https://doi.org/10.1103/PhysRevLett.118.070601