Stability in turbulence: The interplay between shocks and vorticity in a superfluid with higher-order dispersion
Stability in turbulence: The interplay between shocks and vorticity in a superfluid with higher-order dispersion
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DOI：
10.1103/physreva.102.053310
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发表时间：
2020-04
影响因子：
2.9
通讯作者：
M. Mossman;E. Delikatny;M. Forbes;P. Engels
中科院分区：
文献类型：
--
作者：
M. Mossman;E. Delikatny;M. Forbes;P. Engels
高阶色散可以导致有趣的动力学，正成为现代流体力学研究的焦点。这样的系统自然发生，例如在浅水波和非线性光学，其中几种类型的新型色散激波结构已被确定。在这里，我们介绍了超冷原子作为一个可调的量子模拟平台的高阶系统。简并量子气体是超流体中色散流体力学实验研究的良好控制模型系统，并已被用于研究涡旋、孤子、色散激波和量子湍流等现象。随着拉曼诱导自旋轨道耦合的出现，稀气体玻色-爱因斯坦凝聚体的色散可以以灵活的方式进行修改，从而可以详细研究高阶色散动力学。在这里，我们提出了一个相结合的实验和理论研究在这样的系统中产生的冲击结构。自旋-轨道耦合对伽利略不变性的破坏使得两种不同类型的激波结构可以同时出现在一个系统中。数值模拟表明，这些激波结构的行为的影响与涡的相互作用的方式让人想起新兴的粘性流体动力学由于在系统中的底层量子湍流。这一结果表明，自旋-轨道耦合可以作为一个强大的手段来调谐的有效粘度冷原子实验作为湍流流体动力学的量子模拟器，从凝聚态和光学中子星的量子模拟的应用。
Higher-order dispersion can lead to intriguing dynamics that are becoming a focus of modern hydrodynamics research. Such systems occur naturally, for example in shallow water waves and nonlinear optics, for which several types of novel dispersive shocks structures have been identified. Here we introduce ultracold atoms as a tunable quantum simulations platform for higher-order systems. Degenerate quantum gases are well controlled model systems for the experimental study of dispersive hydrodynamics in superfluids and have been used to investigate phenomena such as vortices, solitons, dispersive shock waves and quantum turbulence. With the advent of Raman-induced spin-orbit coupling, the dispersion of a dilute gas Bose-Einstein condensate can be modified in a flexible way, allowing for detailed investigations of higher-order dispersion dynamics. Here we present a combined experimental and theoretical study of shock structures generated in such a system. The breaking of Galilean invariance by the spin-orbit coupling allows two different types of shock structures to emerge simultaneously in a single system. Numerical simulations suggest that the behavior of these shock structures is affected by interactions with vortices in a manner reminiscent of emerging viscous hydrodynamics due to an underlying quantum turbulence in the system. This result suggests that spin-orbit coupling can be used as a powerful means to tun the effective viscosity in cold-atom experiments serving as quantum simulators of turbulent hydrodynamics, with applications from condensed matter and optics to quantum simulations of neutron stars.