Symmetry breaking Rayleigh-Taylor instability in a two-component Bose-Einstein condensate

Rayleigh-Taylor instability and mushroom-pattern formation in a two-component Bose-Einstein condensate

The Rayleigh-Taylor instability at the interface in an immiscible two-component Bose-Einstein condensate is investigated using the mean-field and Bogoliubov theories. Rayleigh-Taylor fingers are found to grow from the interface and mushroom patterns are formed. Quantized vortex rings and vortex lines are then generated around the mushrooms. The Rayleigh-Taylor instability and mushroom-pattern formation can be observed in a trapped system.

Rayleigh-Taylor instability of binary condensates

We propose a scheme to initiate and examine Rayleigh-Taylor instability in the two species Bose-Einstein condensates. We identify $^{85}$Rb-$^{87}$Rb mixture as an excellent candidate to observe it experimentally. The instability is initiated by tuning the $^{85}$Rb-$^{85}$Rb interaction through magnetic Feshbach resonance. We show that the observable signature of the instability is the damping of the radial oscillation. This would perhaps be one of the best controlled experiments on Rayleigh-Taylor instability. We also propose a semi analytic scheme to determinate stationary state of binary c…

Mode bifurcation in the Rayleigh-Taylor instability of binary condensates

We examine the generation and subsequent evolution of Rayleigh Taylor instability in anisotropic binary Bose-Einstein condensates. Considering a pancake-shaped geometry, to initiate the instability we tune the intraspecies interaction and analytically study the normal modes of the interface in elliptic cylindrical coordinates. The normal modes are then Mathieu functions and undergoes bifurcation at particular values of anisotropy and ratio of number of atoms. We find that the analytical estimates of the bifurcation parameters are in good agreement with the numerical results.

Quantum swapping of immiscible Bose-Einstein condensates as an alternative to the Rayleigh-Taylor instability

We consider a two-component Bose-Einstein condensate in a quasi-one-dimensional harmonic trap, where the immiscible components are pressed against each other by an external magnetic force. The zero-temperature non-stationary Gross-Pitaevskii equations are solved numerically; analytical models are developed for the key steps in the process. We demonstrate that if the magnetic force is strong enough, then the condensates may swap their places in the trap due to dynamic quantum interpenetration of the nonlinear matter waves. The swapping is accompanied by development of a modulational instability…

相分离的三分量玻色-爱因斯坦凝聚中的瑞利-泰勒不稳定性

Rayleigh-Taylor instability in a phase-separated three-component Bose-Einstein condensate

本文在平均场框架下研究了相分离三分量玻色-爱因斯坦凝聚中两个界面的瑞利-泰勒不稳定性，发现调节原子间相互作用会破坏旋转对称性，产生指数增长的蘑菇状非线性图案，并将其对应为角马蒂厄方程的简正模解。

Turbulence in Binary Bose-Einstein Condensates Generated by Highly Non-Linear Rayleigh-Taylor and Kelvin-Helmholtz Instabilities

Quantum turbulence (QT) generated by the Rayleigh-Taylor instability in binary immiscible ultracold 87Rb atoms at zero temperature is studied theoretically. We show that the quantum vortex tangle is qualitatively different from previously considered superfluids, which reveals deep relations between QT and classical turbulence. The present QT may be generated at arbitrarily small Mach numbers, which is a unique property not found in previously studied superfluids. By numerical solution of the coupled Gross-Pitaevskii equations we find that the Kolmogorov scaling law holds for the incompressible…