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arXiv · 1003.4641

Bose-Einstein Condensation and Spin Mixtures of Optically Trapped Metastable Helium

G. B. Partridge·J. -C. Jaskula·M. Bonneau·D. Boiron·C. I. Westbrook
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Abstract

We report the realization of a BEC of metastable helium-4 atoms (4He*) in an all optical potential. Up to 10^5 spin polarized 4He* atoms are condensed in an optical dipole trap formed from a single, focused, vertically propagating far off-resonance laser beam. The vertical trap geometry is chosen to best match the resolution characteristics of a delay-line anode micro-channel plate detector capable of registering single He* atoms. We also confirm the instability of certain spin state combinations of 4He* to two-body inelastic processes, which necessarily affects the scope of future experiments using optically trapped spin mixtures. In order to better quantify this constraint, we measure spin state resolved two-body inelastic loss rate coefficients in the optical trap.

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G. B. Partridge, J. -C. Jaskula, M. Bonneau, D. Boiron, C. I. Westbrook. 2010-03-24. Bose-Einstein Condensation and Spin Mixtures of Optically Trapped Metastable Helium. https://doi.org/10.1103/physreva.81.053631

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