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arXiv · 2202.06341

Amplifying quantum correlations with quench dynamics in a quantum spin chain: Steady-states versus ground-states

Sasan Kheiri·Hadi Cheraghi·Saeed Mahdavifar
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Abstract

We analyze the behavior of steady-state quantum correlations (QCs) in the spin-1/2 transverse field XY chains analytically, in terms of quench dynamics at zero-temperature. We show that steady-state QCs are strikingly greater than the equilibrium ones in its ground-state, where a single quench is performed from ferro- into para-magnetic phases. Another framework to amplify the QCs here is a feasible protocol called double quench dynamics. To fulfill this purpose, we probe a middle quench point and spending time T (defined as the time passing from the middle quench point before reaching a second quench). By doing so, both single and double quenches act as practical tools to control the enhancement of the steady-state QCs in the final quenched point. In particular, and in parallel to expectations for some other quantities, we indicate that the nonequilibrium quantum phase transitions also can be identified by nonanalyticities in the steady-state QCs. Our work may be testable with the current class of trapped-ion or ultracold-atom experiments, and encourage the possible potential in the quantum information field.

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Sasan Kheiri, Hadi Cheraghi, Saeed Mahdavifar. 2022-04-20. Amplifying quantum correlations with quench dynamics in a quantum spin chain: Steady-states versus ground-states. https://doi.org/10.1016/j.physa.2022.128314

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