Quasi 1D Bose-Einstein condensate flow past a nonlinear barrier

Abstract

The problem of a quasi 1D {\it repulsive} BEC flow past through a nonlinear barrier is investigated. Two types of nonlinear barriers are considered, wide and short range ones. Steady state solutions for the BEC moving through a wide repulsive barrier and critical velocities have been found using hydrodynamical approach to the 1D Gross-Pitaevskii equation. It is shown that in contrast to the linear barrier case, for a wide {\it nonlinear} barrier an interval of velocities $0<v<v_{-}$ {\it always} exists, where the flow is superfluid regardless of the barrier potential strength. For the case of the $\delta$ function-like barrier, below a critical velocity two steady solutions exist, stable and unstable one. An unstable solution is shown to decay into a gray soliton moving upstream and a stable solution. The decay is accompanied by a dispersive shock wave propagating downstream in front of the barrier.

6 pages, 7 figures, extended abstract, revised arguments in Sects 2,3 results unchanged, added references

References in corpus (3)

• Stationary and non-stationary fluid flow of a Bose-Einstein condensate through a penetrable barrier
• Generation of dispersive shock waves by the flow of a Bose-Einstein condensate past a narrow obstacle
• Quasi-one-dimensional flow of polariton condensate past an obstacle

Cited by in corpus (2)

• Dynamics of defect-induced dark solitons in an exciton-polariton condensate
• Increasing the stability of a superfluid in a rotating necklace potential