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arXiv · 1607.02406

Competition between Bose Einstein Condensation and spin dynamics

Bruno Naylor·Miroslaw Brewczyk·Mariusz Gajda·Olivier Gorceix·Etienne Marechal·Laurent Vernac·Bruno Laburthe-Tolra
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Abstract

We study the impact of spin-exchange collisions on the dynamics of Bose-Einstein condensation, by rapidly cooling a chromium multi-component Bose gas. Despite relatively strong spin-dependent interactions, the critical temperature for Bose-Einstein condensation is reached before the spin-degrees of freedom fully thermalize. The increase in density due to Bose-Einstein condensation then triggers spin dynamics, hampering the formation of condensates in spin excited states. Small metastable spinor condensates are nevertheless produced, and manifest strong spin fluctuations.

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Bruno Naylor, Miroslaw Brewczyk, Mariusz Gajda, Olivier Gorceix, Etienne Marechal, Laurent Vernac, Bruno Laburthe-Tolra. 2016-07-08. Competition between Bose Einstein Condensation and spin dynamics. https://doi.org/10.1103/physrevlett.117.185302

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