Oscillations of a Bose-Einstein condensate rotating in a harmonic plus quartic trap

Abstract

We study the normal modes of a two-dimensional rotating Bose-Einstein condensate confined in a quadratic plus quartic trap. Hydrodynamic theory and sum rules are used to derive analytical predictions for the collective frequencies in the limit of high angular velocities, $\Omega$, where the vortex lattice produced by the rotation exhibits an annular structure. We predict a class of excitations with frequency $\sqrt{6}\Omega$ in the rotating frame, irrespective of the mode multipolarity $m$, as well as a class of low energy modes with frequency proportional to $|m|/\Omega$. The predictions are in good agreement with results of numerical simulations based on the 2D Gross-Pitaevskii equation. The same analysis is also carried out at even higher angular velocities, where the system enters the giant vortex regime.

4 pages, 2 figures

References in corpus (13)

• Driving Bose-Einstein condensate vorticity with a rotating normal cloud
• Vortex states of rapidly rotating dilute Bose-Einstein condensates
• Rotating vortex lattice in a Bose-Einstein condensate trapped in combined quadratic and quartic radial potentials
• Quantized vortices and collective oscillations of a trapped Bose condensed gas
• Rapid rotation of a Bose-Einstein condensate in a harmonic plus quartic trap
• Multiply quantized vortices in trapped Bose-Einstein condensates
• Giant vortices in combined harmonic and quartic traps
• Rapidly rotating Bose-Einstein condensates in anharmonic potentials
• Shape oscillation of a rotating Bose-Einstein condensate
• Macroscopic dynamics of a Bose-Einstein condensate containing a vortex lattice
• Phases of a rotating Bose-Einstein condensate with anharmonic confinement
• Vortices in Bose-Einstein condensates with anharmonic confinement
• Hysteresis and persistent currents in a rotating Bose-Einstein condensate with anharmonic confinement

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• Geometric scale invariance as a route to macroscopic degeneracy: loading a toroidal trap with a Bose or Fermi gas
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