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

S. Giovanazzi·L. Santos·T. Pfau
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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 $ε_{dd}$ of dipolar and s-wave coupling constants. Measuring the differences in the frequencies for different polarization we can extract the value of $ε_{dd}$ 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.

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S. Giovanazzi, L. Santos, T. Pfau. 2006-08-13. Collective oscillations of dipolar Bose-Einstein condensates and accurate comparison between contact and dipolar interaction. https://doi.org/10.1103/physreva.75.015604

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