Bathtub vortex in superfluid He4
Bathtub vortex in superfluid He4
复制标题
超流体 He4 中的浴缸涡流
DOI：
10.1103/physrevb.102.224511
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发表时间：
2020
影响因子：
3.7
通讯作者：
Tsubota Makoto
中科院分区：
文献类型：
--
作者：
Inui Sosuke;Nakagawa Tomo;Tsubota Makoto
我们研究了超流体中宏观吸力流的结构。在这项研究中，我们主要分析量子化涡束的结构，它似乎在这样的系统中扮演着重要的角色。我们的研究是由大阪城市大学的一个研究小组最近进行的一系列实验推动的[Yano，J.Phys.：conf.先生。969,012002(2018)1742-658810.1088/1742-6596/969/1/012002]；他们利用超流体中的转子创造了一个吸力涡流。他们还报告说，在旋转流动的中心区域积累了多达量化的涡流。这种宏观流动中的量子化旋涡被认为是一种束状结构，但其机制尚未得到充分的研究。因此，我们规定了正常流体的宏观吸力流，并讨论了巨涡(即循环量子数超过1的涡旋)和由少量种子涡演化而来的单量子化涡束的演化。然后，通过数值模拟，我们讨论了这种流动中涡束的几种可能的特征结构，并建议可以通过测量宏观正常流动被切断后涡束的扩散常数来验证实验中实际的稳态涡束结构。通过应用超流系统的广泛知识，我们阐明了一种宏观超流流动，并确定了一种量子化的涡旋结构。
We have investigated the structure of macroscopic suction flows in superfluid. In this study, we primarily analyze the structure of the quantized vortex bundle that appears to play an important role in such systems. Our study is motivated by a series of recent experiments conducted by a research group at Osaka City University [Yano , J. Phys.: Conf. Ser. 969, 012002 (2018)1742-658810.1088/1742-6596/969/1/012002]; they created a suction vortex using a rotor in superfluid. They also reported that up toquantized vortices accumulated in the central region of the rotating flow. The quantized vortices in such macroscopic flows are assumed to form a bundle structure; however, the mechanism has not yet been fully investigated. Therefore, we prescribe a macroscopic suction flow to the normal fluid and discuss the evolution of a giant vortex (i.e., one with a circulation quantum number exceeding unity) and a bundle of singly quantized vortices from a small number of seed vortices. Then, using numerical simulations, we discuss several possible characteristic structures of the bundle in such a flow, and we suggest that the actual steady-state bundle structure in the experiment can be verified by measuring the diffusion constant of the vortex bundle after the macroscopic normal flow has been switched off. By applying extensive knowledge of the superfluidsystem, we elucidate a type of macroscopic superfluid flow and identify a structure of quantized vortices.