论文标题
湍流的玻璃凝结物的熵
Entropy of a Turbulent Bose-Einstein Condensate
论文作者
论文摘要
量子湍流涉及量子流体中湍流的现象，例如超流体氦气和被困的Bose-Einstein冷凝物（BEC）。尽管在理解量子动荡方面取得了很多进展，但仍有几个基本问题要回答。在这项工作中，我们调查了一个被困的BEC的熵，其中包括平衡，小型激发，湍流的发作和湍流状态。我们考虑了系统扰动时的时间演变，并在关闭外部激发后开始演化。我们得出了与可访问的实验数据一致的熵的表达式，即使用动量分布是众所周知的假设。我们将激发幅度与扰动系统的不同阶段相关联，我们发现了每个熵的不同特征。特别是，我们观察到建立粒子级联反应后的熵突然增加。我们认为，熵和相关数量可用于研究和表征量子湍流。
Quantum turbulence deals with the phenomenon of turbulence in quantum fluids, such as superfluid helium and trapped Bose-Einstein condensates (BECs). Although much progress has been made in understanding quantum turbulence, several fundamental questions remain to be answered. In this work, we investigated the entropy of a trapped BEC in several regimes, including equilibrium, small excitations, the onset of turbulence, and a turbulent state. We considered the time evolution when the system is perturbed and let to evolve after the external excitation is turned off. We derived an expression for the entropy consistent with the accessible experimental data, that is, using the assumption that the momentum distribution is well-known. We related the excitation amplitude to different stages of the perturbed system, and we found distinct features of the entropy in each of them. In particular, we observed a sudden increase in the entropy following the establishment of a particle cascade. We argue that entropy and related quantities can be used to investigate and characterize quantum turbulence.
