Laser Physics Letters

Nonlocal advantage of quantum coherence in the spin-1/2 and spin-1 Heisenberg XXZ models

Yu-Xia Xie, Yuhan Zhang

Published Feb 5, 2020• 7 citations

Abstract

Abstract Quantum coherence underlies different forms of quantum correlations. We investigate the nonlocal advantage of quantum coherence (NAQC) for the thermal equilibrium states of both the spin-1/2 and the spin-1 Heisenberg XXZ models. By considering the NAQC formulated within two slightly different frameworks, we showed that their values can always be enhanced by tuning strength of the spin-exchange interaction along the z direction. The maximum achievable NAQC by tuning decreases with the increasing temperature T and there will be no NAQC when T is higher than a critical value. Moreover, both the NAQC and the critical temperature could be further noticeably increased by introducing the Dzyaloshinsky–Moriya interaction along either the z direction or the x direction to the considered spin models.

DOI: 10.1088/1612-202x/ab6aa4

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