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arXiv · 1206.4847

Quantum discord and entanglement in Heisenberg XXZ spin chain after quenches

Jie Ren·Yin-Zhong Wu·Shi-Qun Zhu
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Abstract

Using the adaptive time-dependent density-matrix renormalization group method, the dynamics of entanglement and quantum discord of a one-dimensional spin-1/2 XXZ chain is studied when anisotropic interaction quenches are applied at different temperatures. The dynamics of the quantum discord and pairwise entanglement between the nearest qubits shows that the entanglement and quantum discord will first oscillate and then approach to a constant value. The quantum discord can be used to predict the quantum phase transition, while the entanglement cannot.

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Jie Ren, Yin-Zhong Wu, Shi-Qun Zhu. 2012-06-21. Quantum discord and entanglement in Heisenberg XXZ spin chain after quenches. https://doi.org/10.1088/0256-307x%2F29%2F6%2F060305

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