Vorticity Distribution in Quantum Kelvin-Helmholtz Instability of Binary Bose?Einstein Condensates
Vorticity Distribution in Quantum Kelvin-Helmholtz Instability of Binary Bose?Einstein Condensates
复制标题
二元玻色爱因斯坦凝聚量子开尔文-亥姆霍兹不稳定性中的涡度分布
DOI：
10.1007/s10909-021-02660-1
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发表时间：
2022
影响因子：
2
通讯作者：
Takeuchi Hiromitsu
中科院分区：
文献类型：
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作者：
Kokubo Haruya;Kasamatsu Kenichi;Takeuchi Hiromitsu
通过对Gross-Pitaevskii方程的数值分析，研究了分相双组分玻色-爱因斯坦凝聚体中剪切流动不稳定性引起的涡度分布和涡的动力学。我们以前的研究用韦伯数We来分类界面的模式形成，韦伯数We是通过扩展经典流体中的开尔文-亥姆霍兹不稳定性理论来定义的。在具有剪切流动的双组分超流体的直界面上，存在一个涡量的扁平分布，称为涡片。当这个旋涡片像手指一样变形时，在手指的尖端产生量子化的涡流。另一方面，对于，涡片的微观性质变得更加重要，其中涡度分布和涡的产生表现出与对于不同的动力学。当界面较大时，涡量形成条形结构，旋涡-反涡对随之形成。当相对速度较快时，由于局部涡量还没有达到单量子循环，所以涡不能从界面释放到体中。
We study the dynamics of vorticity distribution and vortex generation induced by shear flow instability in a phase-separated two-component Bose–Einstein condensate by means of numerical analysis of the Gross–Pitaevskii equations. Our previous study has classified the pattern formation of the interface by the Weber number We, defined by extending the theory on the Kelvin–Helmholtz instability in classical fluids. On the straight interface of a two-component superfluid with shear flow, there is a flat distribution of vorticity called a vortex sheet. When, this vortex sheet deforms like a finger and quantized vortices are generated at the tip of the fingers. On the other hand, for, the microscopic properties in the vortex sheet become more important, where the vorticity distribution and vortex generation show different dynamics from that for. When the interface is large, the vorticity forms a stripe structure and vortex–antivortex pair formation subsequently occurs. When the relative velocity is fast, vortices cannot be released from the interface into the bulk because the localized vorticity has not reached the single quantum circulation.