Communications in Theoretical Physics

Quantum Correlations in Heisenberg XY Chain

Yinyan Zhu, Yong Zhang

Published Apr 1, 2013• 4 citations

Abstract

Quantum correlations measured by quantum discord (QD), measurement-induced distance (MID), and geometric measure of quantum discord (GMQD) in two-qubit Heisenberg XY spin chain are investigated. The effects of DM interaction and anisotropic on the three correlations are considered. Characteristics of various correlation measures for the two-qubit states are compared. The increasing D z increases QD, MID and GMQD monotonously while the increasing anisotropy both increases and decreases QD and GMQD. The three quantum correlations are always existent at very high temperature. MID is always larger than QD, but there is no definite ordering between QD and GMQD.

DOI: 10.1088/0253-6102/59/4/04

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