Generation of large clouds of ultracold metastable helium

ORAL

Abstract

Metastable helium is buffer-gas cooled, magnetically trapped and evaporatively cooled in large numbers. $10^{11}$ $^{4}He^{*}$ atoms are trapped at an initial temperature of 400 mK and evaporatively cooled into the ultracold regime, resulting in a cloud of $2x10^{9}$ atoms at 1.4 mK. Efficient evaporation indicates low collisional loss for $^{4}He^{*}$ in both the ultracold and multi-partial-wave regime, in agreement with theory. Further evaporative cooling to quantum degeneracy should be attainable after transfering the cloud to an Ioffe-Pritchard trap and implementing RF evaporation.

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Authors

  • S. Charles Doret

    Dept. of Physics, Harvard University

  • Scott V. Nguyen

  • Colin B. Connolly

  • Robert A. Michniak

    Dept. of Physics, Harvard University

  • Wolfgang Ketterle

    MIT, MIT-Harvard Center for Ultracold Atoms, Research Laboratory of Electronics, MIT, Dept. of Physics, MIT, Massachusetts Institute of Technology

  • John M. Doyle

    Dept. of Physics, Harvard University