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Pis'ma v Zhurnal Èksperimental'noi i Teoreticheskoi Fiziki, 2006, Volume 84, Issue 9, Pages 605–609
(Mi jetpl1182)
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This article is cited in 1 scientific paper (total in 1 paper)
CONDENSED MATTER
Coherence and recombination in two-dimensional atomic hydrogen on the surface of superfluid 4He
A. I. Safonov, S. S. Demukh, I. I. Safonova, I. I. Lukashevich Russian Research Centre "Kurchatov Institute"
Abstract:
Experimental results on the achievement of high degrees of quantum degeneration in two-dimensional atomic hydrogen (2D H↓) by the magnetic-compression method are analyzed by taking into account current data on the binding energy E a = 1.14(1) K of hydrogen atoms with the 4He surface and the constant K ab of the two-particle exchange recombination of adsorbed H atoms. The behavior of pair and three-particle correlation functions, as well as the transverse delocalization of the wavefunction of adsorbed atoms due to their interaction with each other, is taken into account self-consistently. A new mechanism of cooling of the compression region by means of the flow of H atoms on the helium surface with the subsequent evaporation and emission from a magnetic trap is proposed. This mechanism prevails at high densities, whereas the heat transfer at low densities occurs owing mainly to the interaction of ripplons with the phonons of the helium film. Existing data corroborate the achievement of the phase density σλ2 ≳ 10, which is certainly higher than the density necessary for both the arrangement of local coherence in 2D H↓ and its transition to the superfluid state. The results agree with the representations on quasi-condensation; however, direct evidence of this phenomenon is not revealed. The probability of three-particle dipole recombination that is corrected for the quantum correlation and delocalization is equal to 7(2) × 10−26 cm4 s−1 (T = 0.15, …, 0.21 K, B = 6.6 T, and σλ2 = 1, …, 9). The results are compared with other theoretical and experimental data.
Received: 28.09.2006
Citation:
A. I. Safonov, S. S. Demukh, I. I. Safonova, I. I. Lukashevich, “Coherence and recombination in two-dimensional atomic hydrogen on the surface of superfluid 4He”, Pis'ma v Zh. Èksper. Teoret. Fiz., 84:9 (2006), 605–609; JETP Letters, 84:9 (2006), 513–517
Linking options:
https://www.mathnet.ru/eng/jetpl1182 https://www.mathnet.ru/eng/jetpl/v84/i9/p605
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