Superfluid flow past an obstacle in annular Bose–Einstein condensates. (4th November 2016)

• Record Type: Journal Article
• Authors: Syafwan, M; Kevrekidis, P; Paris-Mandoki, A; Lesanovsky, I; Krüger, P; Hackermüller, L; Susanto, H
• Is Part Of: Journal of physics. Volume 49:Number 23(2016:Dec. 01)
• Publication Date: 2016-11-04
• Subjects: Bose–Einstein condensates -- dark solitons -- saddle-center bifurcation -- critical velocity; 03.75.Kk -- 67.85.-d -- 37.10.Vz -- 47.37.+q; Atoms -- Periodicals; Molecules -- Periodicals; Optics -- Periodicals; Nuclear physics -- Periodicals; 539.6
• DOI: 10.1088/0953-4075/49/23/235301
• Languages: English
• ISSNs: 0953-4075

Abstract

Abstract: We investigate the flow of a one-dimensional nonlinear Schrödinger model with periodic boundary conditions past an obstacle, motivated by recent experiments with Bose–Einstein condensates in ring traps. Above certain rotation velocities, localized solutions with a nontrivial phase profile appear. In striking difference from the infinite domain, in this case there are many critical velocities. At each critical velocity, the steady flow solutions disappear in a saddle-center bifurcation. These interconnected branches of the bifurcation diagram lead to additions of circulation quanta to the phase of the associated solution. This, in turn, relates to the manifestation of persistent current in numerous recent experimental and theoretical works, the connections to which we touch upon. The complex dynamics of the identified waveforms and the instability of unstable solution branches are demonstrated.