Studies with Ultracold Metastable Hydrogen
This thesis describes the first detailed studies of trapped metastable (2S-state) hydrogen.
physics.atom-ph↗
arXiv subjects
David Landhuis
Publications and source records attributed to David Landhuis.
Bose-Einstein Condensation of Atomic Hydrogen
We have observed Bose-Einstein condensation (BEC) of trapped atomic hydrogen, and studied it by two-photon spectroscopy of the 1S-2S transition. In these lecture notes we briefly review the history of spin-polarized atomic hydrogen and describe the final steps to BEC. Laser spectroscopy, which probes the difference in mean field energy of the 1S and 2S states, is used to study the condensate, which has a peak density of 4.8e15 cm^-3 and population of 10^9.
physics.atom-ph↗
Cold Collision Frequency Shift of the 1S-2S Transition in Hydrogen
We have observed the cold collision frequency shift of the 1S-2S transition in trapped spin-polarized atomic hydrogen. We find $Δν_{1S-2S} = -3.8(8)\times 10^{-10} n Hz cm^3$, where $n$ is the sample density. From this we derive the 1S-2S s-wave triplet scattering length, $a_{1S-2S}=-1.4(3)$ nm, which is in fair agreement with a recent calculation. The shift provides a valuable probe of the distribution of densities in a trapped sample.
physics.atom-ph↗
Bose-Einstein Condensation of Atomic Hydrogen
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}.
physics.atom-ph↗