Breakdown of Kohn Theorem Near Feshbach Resonance

Hamid Al-Jibbouri; Axel Pelster

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arXiv · 1306.1988

Breakdown of Kohn Theorem Near Feshbach Resonance

Hamid Al-Jibbouri·Axel Pelster

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Abstract

We study the collective excitation frequencies of a harmonically trapped 85Rb Bose-Einstein condensate (BEC) in the vicinity of a Feshbach resonance. To this end, we solve the underlying Gross-Pitaevskii (GP) equation by using a Gaussian variational approach and obtain the coupled set of ordinary differential equations for the widths and the center of mass of the condensate. A linearization shows that the dipole mode frequency decreases when the bias magnetic field approaches the Feshbach resonance, so the Kohn theorem is violated.

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Hamid Al-Jibbouri, Axel Pelster. 2013-06-09. Breakdown of Kohn Theorem Near Feshbach Resonance. https://arxiv.org/abs/1306.1988

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