Two dimensional bright solitons in dipolar Bose-Einstein condensates with tilted dipoles

CNRS, UMR 7538, LPL, F-93430 Villetaneuse, France(Dated: June 9, 2015)The e ect of dipolar orientation with respect to the soliton plane on the physics of two-dimensional brightsolitons in dipolar Bose-Einstein condensates is discussed. Previous studies on such a soliton involved dipoleseither perpendicular or parallel to the condensate-plane. The tilting angle constitutes an additional tuning pa-rameter, which help us to control the in-plane anisotropy of the soliton as well as provides access to previouslydisregarded regimes of interaction parameters for soliton stability. In addition, it can be used to drive the conden-sate into phonon instability without changing its interaction parameters or trap geometry. The phonon-instabilityin a homogeneous 2D condensate of tilted dipoles always features a transient stripe pattern, which eventuallybreaks into a metastable soliton gas. Finally, we demonstrate how a dipolar BEC in a shallow trap can eventuallybe turned into a self-trapped matter wave by an adiabatic approach, involving the tuning of tilting angle.I. INTRODUCTION