A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Formation of Nuclear-Polarized Phases of H Atoms Embedded in Solid H-2 Films
Tekijät: Sheludiakov S, McColgan PT, Lee DM, Khmelenko VV, Järvinen J, Ahokas J, Vasiliev S
Kustantaja: AMER PHYSICAL SOC
Julkaisuvuosi: 2019
Journal: Physical Review Letters
Tietokannassa oleva lehden nimi: PHYSICAL REVIEW LETTERS
Lehden akronyymi: PHYS REV LETT
Artikkelin numero: ARTN 225301
Vuosikerta: 122
Numero: 22
Sivujen määrä: 5
ISSN: 0031-9007
eISSN: 1079-7114
DOI: https://doi.org/10.1103/PhysRevLett.122.225301
Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/detail/Publication/41276084
We report on an experimental observation of two phases of hydrogen atoms in solid H-2 films at temperatures of 0.1-0.8 K, characterized by a large enhancement of the nuclear spin polarization compared to that given by Boltzmann statistics (p = 0.15 at T = 0.15 K). The first phase with p = 0.35(5) is formed spontaneously during sample storage in a high magnetic field (B = 4.6 T). The second phase with an even higher nuclear polarization, p = 0.75(7), can be achieved at T <= 0.55 K by repeating sequences of dynamic nuclear polarization followed by a system relaxation. Upon warming through the range 0.55-0.65 K, the highly nuclear-polarized phase undergoes a phase transition to the spontaneously polarized phase which breaks down at T similar or equal to 0.8 K, and the nuclear polarization gradually converges to the Boltzmann distribution. We discuss possible scenarios for explaining the nature of the observed phenomena.
Ladattava julkaisu This is an electronic reprint of the original article. |