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arXiv · 0812.4335

Direct evaporative cooling of 41K into a Bose-Einstein condensate

T. Kishimoto·J. Kobayashi·K. Noda·K. Aikawa·M. Ueda·S. Inouye
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Abstract

We have investigated the collisional properties of 41K atoms at ultracold temperature. To show the possibility to use 41K as a coolant, a Bose-Einstein condensate of 41K atoms in the stretched state (F=2, m_F=2) was created for the first time by direct evaporation in a magnetic trap. An upper bound of three body loss coefficient for atoms in the condensate was determined to be 4(2) 10^{-29} cm -6 s-1. A Feshbach resonance in the F=1, m_F=-1 state was observed at 51.42(5) G, which is in good agreement with theoretical prediction.

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T. Kishimoto, J. Kobayashi, K. Noda, K. Aikawa, M. Ueda, S. Inouye. 2008-12-23. Direct evaporative cooling of 41K into a Bose-Einstein condensate. https://doi.org/10.1103/physreva.79.031602

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