arXiv 1010.01092010-10-01quant-ph

Spin Squeezing, Negative Correlations, and Concurrence in the Quantum Kicked Top Model

Xiaoqian Wang, Jian Ma, Lijun Song, Xihe Zhang, Xiaoguang Wang

备注：: 8 pages, 6 figures
发表信息：: Phys. Rev. E 82, 056205 (2010)
DOI：: 10.1103/PhysRevE.82.056205

英文摘要：

We study spin squeezing, negative correlations, and concurrence in the quantum kicked top model. We prove that the spin squeezing and negative correlations are equivalent for spin systems with only symmetric Dicke states populated. We numerically analyze spin squeezing parameters and concurrence in this model, and find that the maximal spin squeezing direction, which refers to the minimal pairwise correlation direction, is strongly influenced by quantum chaos. Entanglement (spin squeezing) sudden death and sudden birth occur alternatively for the periodic and quasi-periodic cases, while only entanglement (spin squeezing) sudden death is found for the chaotic case.

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