Excitations of a vortex line in an elongated dipolar condensate

Stability and excitations of a dipolar Bose-Einstein condensate with a vortex

We study the stability of singly and doubly quantized vortex states of harmonically trapped dipolar BoseEinstein condensates BECs by calculating the low-lying excitations of these condensates. We map the dynamical stability of these vortices as functions of the dipole-dipole interaction strength and trap geometry by finding where their excitations have purely real energy eigenvalues. In contras...

Exotic vortex lattices in a rotating binary dipolar Bose-Einstein condensate

In the last decade, considerable advances have been made in the investigation of dipolar quantum gases. Previous theoretical investigations of a rotating binary dipolar Bose-Einstein condensate, where only one component possesses dipole moment, were mainly focused on two special orientations of the dipoles: perpendicular or parallel to the plane of motion. Here we study the ground-state and rot...

Phase coherence length of an elongated Bose-Einstein condensate

Surface excitations in a Bose-Einstein condensate

Collective modes which have no radial nodes and are localized close to the surface of the condensate are called surface modes. In a semiclassical picture these excitations can be considered the mesoscopic counterpart to tidal waves at the macroscopic level. Those excitations are of special interest since they show a crossover between collective and single-particle behavior, which is crucial for...

Surface excitations of a bose-einstein condensate

Surface modes in a Bose-Einstein condensate of sodium atoms have been studied. We observed excitations of standing and rotating quadrupolar and hexadecapolar modes. The modes were excited with high spatial and temporal resolution using the optical dipole force of a rapidly scanning laser beam. This novel technique is very flexible and should be useful for the study of rotating Bose-Einstein con...