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Reaching the hydrodynamic regime in a Bose-Einstein condensate by suppression of avalanche

K. M. R. van der Stam·R. Meppelink·J. M. Vogels·P. van der Straten
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Abstract

We report the realization of a Bose-Einstein condensate (BEC) in the hydrodynamic regime. The hydrodynamic regime is reached by evaporative cooling at a relative low density suppressing the effect of avalanches. With the suppression of avalanches a BEC containing 120.10^6 atoms is produced. The collisional opacity can be tuned from the collisionless regime to a collisional opacity of more than 3 by compressing the trap after condensation. In the collisional opaque regime a significant heating of the cloud at time scales shorter than half of the radial trap period is measured. This is direct proof that the BEC is hydrodynamic.

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K. M. R. van der Stam, R. Meppelink, J. M. Vogels, P. van der Straten. 2006-09-07. Reaching the hydrodynamic regime in a Bose-Einstein condensate by suppression of avalanche. https://doi.org/10.1103/physreva.75.031602

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