Revealing missing charges with generalised quantum fluctuation relations

Autor: Mur-Petit, J., Relaño, A., Molina, R. A., Jaksch, D.
Rok vydání: 2017
Předmět:
Zdroj: Nat. Commun. 9, 2006 (2018)
Druh dokumentu: Working Paper
DOI: 10.1038/s41467-018-04407-1
Popis: The non-equilibrium dynamics of quantum many-body systems is one of the most fascinating problems in physics. Open questions range from how they relax to equilibrium to how to extract useful work from them. A critical point lies in assessing whether a system has conserved quantities (or 'charges'), as these can drastically influence its dynamics. Here we propose a general protocol to reveal the existence of charges based on a set of exact relations between out-of-equilibrium fluctuations and equilibrium properties of a quantum system. We apply these generalised quantum fluctuation relations to a driven quantum simulator, demonstrating their relevance to obtain unbiased temperature estimates from non-equilibrium measurements. Our findings will help guide research on the interplay of quantum and thermal fluctuations in quantum simulation, in studying the transition from integrability to chaos and in the design of new quantum devices.
Comment: v3: substantially improved presentation and discussion, matches published version; accompanied by numerical data in figures
Databáze: arXiv