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arXiv · 2002.00230

Dynamics of Quantum Coherence and Quantum Fisher Information After Sudden Quench

R. Jafari·Alireza Akbari
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Abstract

The dynamics of relative entropy and $l_{1}$-norm of coherence, as well as, the Wigner-Yanase-skew and quantum Fisher information are studied for a time-dependent coupled XY spin chain in presence of a time-dependent transverse magnetic field. Independent of the initial state of the system and while the relative entropy of coherence, $l_{1}$-norm of coherence, and quantum Fisher information are incapable, surprisingly, the dynamic Wigner-Yanase-skew information can truly spotlight the equilibrium critical point. We also observe that when the system is quenched to the critical point, these quantities show suppressions and revivals. Moreover, the first suppression (revival) time scales linearly with the system size and its scaling ratio is unique for all quenches independent to the initial phase. This is the promised universality of the first suppression (revival) time.

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R. Jafari, Alireza Akbari. 2020-02-01. Dynamics of Quantum Coherence and Quantum Fisher Information After Sudden Quench. https://doi.org/10.1103/physreva.101.062105

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