Nonequilibrium states of a quenched Bose gas
Nonequilibrium states of a quenched Bose gas
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DOI：
10.1103/physreva.90.063626
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发表时间：
2014-12-17
影响因子：
2.9
通讯作者：
Ling, Hong Y.
中科院分区：
文献类型：
--
作者：
Kain, Ben;Ling, Hong Y.
Yin和Radzihovsky [ X. Yin和L. Radzihovsky，Phys.Rev.A88，063611（2013）]最近开发了Bogoliubov理论的自洽扩展，其中凝聚体数密度n（c）被视为随时间变化的平均场，以便分析Makotyn等人的JILA实验[P. Makotyn等人，10，116（2014）]在Rb-85玻色气体上，在深度淬灭到大散射长度之后。我们应用这一理论来构造一组封闭的方程，突出了（n）在点（c）上的作用，即诱导准粒子之间的有效相互作用。我们分析表明，这样的系统支持一个稳定的状态，其特征在于由一个恒定的凝聚密度和一个稳定的，但定期变化的动量分布，其时间平均描述的广义吉布斯系综。我们讨论了如何（n）在点（c）诱导的有效相互作用，这不能被忽略的理由的绝热近似的模式附近的无隙戈德斯通模式，可以显着影响凝聚人口和谭的接触玻色气体，经历了深淬火。
Yin and Radzihovsky [ X. Yin and L. Radzihovsky, Phys. Rev. A 88, 063611 (2013)] recently developed a self-consistent extension of a Bogoliubov theory, in which the condensate number density n(c) is treated as a mean field that changes with time, in order to analyze a JILA experiment by Makotyn et al. [ P. Makotyn et al., Nat. Phys. 10, 116 (2014)] on a Rb-85 Bose gas following a deep quench to a large scattering length. We apply this theory to construct a closed set of equations that highlight the role of (n) over dot(c), which is to induce an effective interaction between quasiparticles. We show analytically that such a system supports a steady state characterized by a constant condensate density and a steady but periodically changing momentum distribution, whose time average is described exactly by the generalized Gibbs ensemble. We discuss how the (n) over dot(c)-induced effective interaction, which cannot be ignored on the grounds of the adiabatic approximation for modes near the gapless Goldstone mode, can significantly affect condensate populations and Tan's contact for a Bose gas that has undergone a deep quench.