Instabilities of a Filled Vortex in a Two-Component Bose–Einstein Condensate

A two-component Bose–Einstein condensate of cold atoms with a strong intercomponent repulsion leading to the spatial separation components has been numerically studied. Configurations multiple quantized vortex in one component, where core is filled other are considered. The effective radius can exceed width transition layer between components, and then an analogy cylindrical classical hydrodynamics two immiscible ideal fluids appears. This allows analyze longitudinal “sausage” instability transverse caused by “tangential discontinuity,” as well stable regime parametric gap them. presence long-lived coherent structures formed some cases at nonlinear stages both instabilities discovered.