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arXiv · 2010.03752

Easy access to energy fluctuations in non-equilibrium quantum many-body systems

Marcela Herrera·John P. S. Peterson·Roberto M. Serra·Irene D'Amico
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Abstract

We combine theoretical and experimental efforts to propose a method for studying energy fluctuations, in particular, to obtain the related bi-stochastic matrix of transition probabilities by means of simple measurements at the end of a protocol that drives a many-body quantum system out-of-equilibrium. This scheme is integrated with numerical optimizations in order to ensure a proper analysis of the experimental data, leading to physical probabilities. The method is experimentally evaluated employing a two interacting spin-1/2 system in a nuclear magnetic resonance setup. We show how to recover the transition probabilities using only local measures which enables an experimental verification of the detailed fluctuation theorem in a many-body system driven out-of-equilibrium.

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Marcela Herrera, John P. S. Peterson, Roberto M. Serra, Irene D'Amico. 2021-05-26. Easy access to energy fluctuations in non-equilibrium quantum many-body systems. https://doi.org/10.1103/physrevlett.127.030602

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