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arXiv · 0710.3643

Stabilizing a purely dipolar quantum gas against collapse

T. Koch·T. Lahaye·J. Metz·B. Fröhlich·A. Griesmaier·T. Pfau
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Abstract

We report on the experimental observation of the dipolar collapse of a quantum gas which sets in when we reduce the contact interaction below some critical value using a Feshbach resonance. Due to the anisotropy of the dipole-dipole interaction, the stability of a dipolar Bose-Einstein condensate depends not only on the strength of the contact interaction, but also on the trapping geometry. We investigate the stability diagram and find good agreement with a universal stability threshold arising from a simple theoretical model. Using a pancake-shaped trap with the dipoles oriented along the short axis of the trap, we are able to tune the scattering length to zero, stabilizing a purely dipolar quantum gas.

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T. Koch, T. Lahaye, J. Metz, B. Fröhlich, A. Griesmaier, T. Pfau. 2007-10-19. Stabilizing a purely dipolar quantum gas against collapse. https://doi.org/10.1038/nphys887

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