Abstract In this paper, we consider the entanglement dynamics of a four-qubit model [2006 Phys. Rev. A 74 042328] where two entangled qubits a and b locally interact with separate qubits A and B via the spin-exchange-like Hamiltonian. We study the effect of purity of initial entangled state of qubits a, b on the entanglement evolution and its relation with energy transfer. Also, we find that the total bipartite entanglement of qubits a, b plus A, B is not a constant any longer when the initial entangled state of a, b is not pure, which is a complement to the result in the paper [2007 J. Phys. B 40 S45] for the pure case.
Received: 14 January 2008
Revised: 23 February 2008
Accepted manuscript online:
Reduction of impurity confinement time by combined heating of LHW and ECRH in EAST Zong Xu(许棕), Zhen-Wei Wu(吴振伟), Ling Zhang(张凌), Yue-Heng Huang(黄跃恒), Wei Gao(高伟), Yun-Xin Cheng(程云鑫), Xiao-Dong Lin(林晓东), Xiang Gao(高翔), Ying-Jie Chen(陈颖杰), Lei Li(黎嫘), Yin-Xian Jie(揭银先), Qing Zang(臧庆), Hai-Qing Liu(刘海庆), and EAST team. Chin. Phys. B, 2021, 30(7): 075205.
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