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Dynamics of evaporative cooling in magnetically trapped atomic hydrogen

Makoto Yamashita·Masato Koashi·Tetsuya Mukai·Masaharu Mitsunaga·Nobuyuki Imoto
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Abstract

We study the evaporative cooling of magnetically trapped atomic hydrogen on the basis of the kinetic theory of a Bose gas. The dynamics of trapped atoms is described by the coupled differential equations, considering both the evaporation and dipolar spin relaxation processes. The numerical time-evolution calculations quantitatively agree with the recent experiment of Bose-Einstein condensation with atomic hydrogen. It is demonstrated that the balance between evaporative cooling and heating due to dipolar relaxation limits the number of condensates to 9x10^8 and the corresponding condensate fraction to a small value of 4% as observed experimentally.

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Makoto Yamashita, Masato Koashi, Tetsuya Mukai, Masaharu Mitsunaga, Nobuyuki Imoto. 2000-07-11. Dynamics of evaporative cooling in magnetically trapped atomic hydrogen. https://doi.org/10.1103/physreva.62.033602

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