Collective oscillations of dipolar Bose-Einstein condensates and accurate comparison between contact and dipolar interaction

Abstract

We propose a scheme for the measurement of the s-wave scattering length $a$ of an atom or molecule with significant dipole-dipole interaction with an accuracy at the percent level. The frequencies of the collective oscillations of a Bose-Einstein condensate are shifted by the magnetic dipole interaction. The shift is polarization dependent and proportional to the ratio ${\epsilon }_{dd}$ of dipolar and s-wave coupling constants. Measuring the differences in the frequencies for different polarization we can extract the value of ${\epsilon }_{dd}$ and thus measure $a$. We calculate the frequency shifts for a large variety of non-axisymmetric harmonic traps in the Thomas-Fermi limit and find optimal trapping geometries to maximize the shifts.

4 pages, brief report

References in corpus (7)

• Bose-Einstein condensation of chromium
• Observation of dipole-dipole interaction in a degenerate quantum gas
• Exact hydrodynamics of a trapped dipolar Bose-Einstein condensate
• Comparing contact and dipolar interaction in a Bose-Einstein condensate
• Expansion dynamics of a dipolar Bose-Einstein condensate
• Instabilities and the roton spectrum of a quasi-1D Bose-Einstein condensed gas with dipole-dipole interactions
• Enhancement of variation of fundamental constants in ultracold atom and molecule systems near Feshbach resonances

Cited by in corpus (8)

• Dipolar physics: A review of experiments with magnetic quantum gases
• Super-Tonks-Girardeau regime in trapped one-dimensional dipolar gases
• Thomas-Fermi versus one- and two-dimensional regimes of a trapped dipolar Bose-Einstein condensate
• Collective excitation frequencies and stationary states of trapped dipolar Bose-Einstein condensates in the Thomas-Fermi regime
• Ground states of spin-3 Bose-Einstein condensates for conserved magnetization
• An effective many-body theory for strongly interacting polar molecules
• Groundstate and Collective Modes of a Spin-Polarized Dipolar Bose-Einstein Condensate in a Harmonic Trap
• Observing collapse in two colliding dipolar Bose-Einstein condensates