title: Exotic behavior of hydrogen atoms in solid H2 at temperatures below 1 K.
abstract: We present the first magnetic resonance study of atomic hydrogen embedded in solid H2 films for temperatures 150-900 mK. We found that at T approximately 150 mK average concentrations of H atoms of order 10(18 cm(-3) are very stable against recombination during two weeks of observations. The distribution of the population of the two lowest hyperfine states is found to be non-Boltzmann, with a very large occupation of the ground state. We consider the possibility of formation in solid H2 of regions with high local concentrations of H atoms, where collective quantum phenomena might occur.
authors.affiliation: Wihuri Physical Laboratory, Department of Physics, University of Turku, 20014 Turku, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Ahokas
authors.forename: J
authors.initials: J
authors.lastname: Järvinen
authors.forename: V V
authors.initials: VV
authors.lastname: Khmelenko
authors.forename: D M
authors.initials: DM
authors.lastname: Lee
authors.forename: S
authors.initials: S
authors.lastname: Vasiliev