文献类型：期刊文献

英文题名：Entanglement dynamics of two qubits coupled by Heisenberg XY interaction under a nonuniform magnetic field in a spin bath

作者：Zhou Feng-Xue[1];Zhang Li-Da[1];Qi Yi-Hong[2];Niu Yue-Ping[1];Zhang Jing-Tao[1];Gong Shang-Qing[1,2]

机构：[1]Chinese Acad Sci, Shanghai Inst Opt & Fine Mech, State Key Lab High Field Laser Phys, Shanghai 201800, Peoples R China;[2]E China Univ Sci & Technol, Dept Phys, Shanghai 200237, Peoples R China

年份：2011

卷号：20

期号：8

外文期刊名：CHINESE PHYSICS B

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000294810700003)】；

基金：Project supported by the National Natural Science Foundation of China (Grant Nos. 10874194, 60978013, and 60921004) and the International Cooperation Program from Science and Technology Commission of Shanghai Municipality (Grant No. 10530704800).

语种：英文

外文关键词：quantum entanglement; decoherence; qubits; Heisenberg model

摘要：This paper investigates the entanglement dynamics of a Heisenberg XY model for a two-spin system in the presence of a nonuniform magnetic field. The master equations and the concurrence evolution equations for the initial alpha state are derived and analysed. It is shown that for the symmetric initial alpha state, only the nonuniform field can play a role in entanglement dynamics while the uniform field and the bath will not play such a role. For the asymmetric alpha state, the nonuniform field leads to the beat pattern oscillation of the concurrence evolution. The inhomogeneity of the field can enhance the entanglement by suppressing the decoherence effects of both the spin-orbit interaction and the spin bath.