Interference of a Bose-Einstein condensate in a hard-wall trap: From the nonlinear Talbot effect to the formation of vorticity

Abstract

We theoretically study the coherent expansion of a BoseEinstein condensate in the presence of a confining impenetrable hard-wall potential. The nonlinear dynamics of the macroscopically coherent matter field results in rich and complex spatio-temporal interference patterns demonstrating the formation of vorticity and solitonlike structures, and the fragmentation of the condensate into coherently coupled pieces. 03.75.Fi,05.30.Jp

Self-interfering matter-wave patterns generated by a moving laser obstacle in a two-dimensional Bose-Einstein condensate inside a power trap cut off by box potential boundaries

“…Note that this is different from the way the box potential was constructed in Ref. [31], where a set of large-amplitude Gaussians was used. In essence, we mimic here an "exact" hard-wall potential where the BEC cannot tunnel −even slightly− through the wall.…”

“…However, our 2D al square box is achieved numerically by a different method than that of the latter authors. The main motivation of this work, then, is largely based on the latter work of Ruostekoski et al [31]. Additional motivation stems from a previous investigation by Jackson et al [1], who simulated the motion of an "object" through a dilute BEC in a 2D al harmonic trap, where the object (or obstacle) corresponds to a laser-induced vortex potential.…”

“…The trap is cut off by hardwall box-potential (HWBP) boundaries serving as reflectors of matter waves. In fact, the box potential, along with other hard-wall trapping geometries, has been used previously by Ruostekoski et al [31], who explored the interference of a BEC in a hard-wall trap plus the nonlinear Talbot effect. We shall comment on their work in the discussion section.…”

Quasiperiodic versus irreversible dynamics of an optically confined Bose-Einstein condensate

“…In a previous paper [9] we studied the dynamics of a condensate inside a simple resonator (modelled by a one dimensional square box) and focused particularly on the influence of the inter atomic interactions on the behavior of the system. We showed that starting from a localized wave packet and by increasing the nonlinearities we pass from a quasi linear regime, where phenomena like nonlinear revivals and fractional revivals are expected [10], to a regime where stochastization of the movement takes place and where the nonlinear revivals of the wave packet are replaced by revivals of regular dynamics.…”

Manifestations of vortices during ultracold-atom propagation through waveguides

“…Vortices are familiar in systems with nonlinear interactions. Ruostekoski et al [14], as a theoretical example, found vortices in an expanding BEC reflecting from the hard walls of a two-dimensional (2D) circular box. Indeed, there are a variety of ways that vortices can be produced in nonlinear optics (see Ref.…”