Enhancement of spin coherence in a spin-1 Bose-Einstein condensate by dynamical decoupling approaches
Enhancement of spin coherence in a spin-1 Bose-Einstein condensate by dynamical decoupling approaches
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通过动态解耦方法增强自旋 1 玻色-爱因斯坦凝聚中的自旋相干性
DOI：
10.1103/physreva.84.013606
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发表时间：
2011-03
影响因子：
2.9
通讯作者：
Zhang, Wenxian
中科院分区：
文献类型：
--
作者：
Ning, Bo-Yuan;Zhuang, Jun;You, J. Q.;Zhang, Wenxian
我们研究了在自旋为1的玻色-爱因斯坦凝聚体中，周期、级联或Uhrig动态解耦N脉冲序列对自旋相干性的增强，其中这种铁磁相互作用凝聚体的本征动力学不稳定性导致自旋退相干，最终导致多重空间域结构或自旋织构。我们的结果表明，这三个序列都成功地将凝聚体中最不稳定模的波矢推到了更大的值，从而成功地增强了自旋相干性。在具有相同脉冲数目的三个序列中，级联序列在保持自旋相干性方面表现出最好的性能。更有趣的是，我们发现这三个序列完全遵循相同的增强规律，k{sub1/2}=c，其中k{sub1/2}是最不稳定模的波矢，T是序列周期，c是序列依赖常数。对于受周期动力学去耦合序列约束的吸引标量玻色-爱因斯坦凝聚体，我们也解析地推导出了k与T之间的这样一个定律。
We study the enhancement of spin coherence with periodic, concatenated, or Uhrig dynamical decoupling N-pulse sequences in a spin-1 Bose-Einstein condensate, where the intrinsic dynamical instability in such a ferromagnetically interacting condensate causes spin decoherence and eventually leads to a multiple spatial-domain structure or a spin texture. Our results show that all three sequences successfully enhance the spin coherence by pushing the wave vector of the most unstable mode in the condensate to a larger value. Among the three sequences with the same number of pulses, the concatenated one shows the best performance in preserving the spin coherence. More interestingly, we find that all three sequences exactly follow the same enhancement law, k{sub -}T{sup 1/2}=c, with k{sub -} the wave vector of the most unstable mode, T the sequence period, and c a sequence-dependent constant. Such a law between k{sub -} and T is also derived analytically for an attractive scalar Bose-Einstein condensate subjected to a periodic dynamical decoupling sequence.