General relaxation time of the fidelity for isolated quantum thermodynamic systems

Takaaki Monnai

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13 Citations (Scopus)


General evaluation of the relaxation time to equilibrium is usually considered as difficult, since it would strongly depend on the model of interest. In this paper, we provide a generic initial relaxation time of the fidelity for the isolated large systems. The decay of the fidelity is a combination of the Lorentzian and a sinusoidal oscillation. We calculate the relaxation time of the Lorentzian envelop, and the period of the oscillation. Remarkably, these two time scales are the same order when the energy range of the microcanonical state is larger than the thermal fluctuation. Also, the power law decay generally exists for long time regime.

Original languageEnglish
Article number064001
JournalJournal of the Physical Society of Japan
Issue number6
Publication statusPublished - 2014 Jun 15


ASJC Scopus subject areas

  • Physics and Astronomy(all)

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