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Bose-Einstein Condensation of Atomic Hydrogen

Dale G. Fried·Thomas C. Killian·Lorenz Willmann·David Landhuis·Stephen C. Moss·Daniel Kleppner·Thomas J. Greytak
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Abstract

We report observation of Bose-Einstein condensation of a trapped, dilute gas of atomic hydrogen. The condensate and normal gas are studied by two-photon spectroscopy of the 1S-2S transition. Interactions among the atoms produce a shift of the resonance frequency proportional to density. The condensate is clearly distinguished by its large frequency shift. The peak condensate density is 4.8 +/- 1.1 \times 10^{15} cm^{-3}, corresponding to a condensate population of 10^9 atoms. The BEC transition occurs at about T=50 uK and n=1.8 \times 10^{14} cm^{-3}.

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Dale G. Fried, Thomas C. Killian, Lorenz Willmann, David Landhuis, Stephen C. Moss, Daniel Kleppner, Thomas J. Greytak. 1998-10-05. Bose-Einstein Condensation of Atomic Hydrogen. https://doi.org/10.1103/physrevlett.81.3811

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