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arXiv · 1304.7362

Odd-even effect of quantum discord and quantum phase transitions in the S=1/2 spin ladder with ring exchange

H. L. Huang·Z. Y. Sun·B. Wang
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Abstract

The singularity of quantum correlations, such as quantum entanglement(QE) and quantum discord(QD), has been widely regarded as a valuable indicator for quantum phase transition(QPT) in low-dimensional quantum systems. In this paper, for a spin ladder system with ring exchange, we find that the singularity of QD (or QE) could not indicate the critical points of the system. Instead, the QD shows a novel odd-even effect in some phases, which can be used to detect the phase boundary points. The size effect is related to the symmetry breaking of the ladder.

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H. L. Huang, Z. Y. Sun, B. Wang. 2013-04-27. Odd-even effect of quantum discord and quantum phase transitions in the S=1/2 spin ladder with ring exchange. https://doi.org/10.1002/pssb.201349047

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