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arXiv · 0908.0248

Bose-Einstein condensation of alkaline earth atoms: $^{40}${Ca}

Sebastian Kraft·Felix Vogt·Oliver Appel·Fritz Riehle·Uwe Sterr
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Abstract

We have achieved Bose-Einstein condensation of $^{40}$Ca, the first for an alkaline earth element. The influence of elastic and inelastic collisions associated with the large ground state s-wave scattering length of $^{40}$Ca was measured. From these findings, an optimized loading and cooling scheme was developed that allowed us to condense about $2 \cdot 10^4$ atoms after laser cooling in a two-stage magneto-optical trap and subsequent forced evaporation in a crossed dipole trap within less than 3 s. The condensation of an alkaline earth element opens novel opportunities for precision measurements on the narrow intercombination lines as well as investigations of molecular states at the $^1$S--$^3$P asymptotes.

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Sebastian Kraft, Felix Vogt, Oliver Appel, Fritz Riehle, Uwe Sterr. 2009-09-02. Bose-Einstein condensation of alkaline earth atoms: $^{40}${Ca}. https://doi.org/10.1103/physrevlett.103.130401

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