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arXiv · 1105.2866

Quantum correlations in spin models

Guo-Feng Zhang·Heng Fan·Ai-Ling Ji·Zhao-Tan Jiang·Ahmad Abliz·Wu-Ming 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 use of measurement-induced disturbance (MID) [Phys. Rev. A, 77, 022301 (2008)] and geometric measure of quantum discord (GQD) [Phys. Rev. Lett. 105, 190502 (2010)]. Their dependencies on external magnetic field, spin-spin coupling, and Dzyaloshinski-Moriya (DM) interaction are presented in detail. We also compare Bell nonlocality, entanglement measured by concurrence, MID and GQD and illustrate their different characteristics.

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Guo-Feng Zhang, Heng Fan, Ai-Ling Ji, Zhao-Tan Jiang, Ahmad Abliz, Wu-Ming Liu. 2011-05-14. Quantum correlations in spin models. https://doi.org/10.1016/j.aop.2011.05.002

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