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DOE OSTI · 21583287

Quantum correlations in spin models

Heng, Fan·Ailing, Ji·Zhaotan, Jiang·Abliz, Ahmad·Wuming, Liu
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Abstract

Bell nonlocality, entanglement and nonclassical correlations are different aspects of quantum correlations for a given state. There are many methods to measure nonclassical correlations. In this paper, nonclassical correlations in two-qubit spin models are measured by the use of measurement-induced disturbance (MID) [S. Luo, Phys. Rev. A 77 (2008) 022301] and geometric measure of quantum discord (GQD) [B. Dakic, V. Vedral, C. Brukner, Phys. Rev. Lett. 105 (2010) 190502]. Their dependences on external magnetic field, spin-spin coupling, and the Dzyaloshinskii-Moriya (DM) interaction are presented in detail. We also compare Bell nonlocality, entanglement measured by concurrence, MID and GQD and illustrate their different characteristics. - Highlights: > Various quantum correlations in spin models are investigated. > Nonclassical correlations are measured by measurement-induced disturbance and Geometric measure of quantum discord. > Also, we investigate Bell nonlocality and concurrence. > We compare these quantum quantities and illustrate their different characteristics.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSANGULAR MOMENTUMCORRELATIONSCOUPLINGDISTURBANCESGEOMETRYINTERACTIONSMAGNETIC FIELDSMATHEMATICSPARTICLE PROPERTIESQUANTUM ENTANGLEMENTSPIN

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Heng, Fan, Ailing, Ji, Zhaotan, Jiang, Abliz, Ahmad, Wuming, Liu. 2011-10-15. Quantum correlations in spin models. https://doi.org/10.1016/j.aop.2011.05.002

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