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Title: Bose-Einstein-condensation temperature of a gas of weakly dissociated diatomic molecules

Abstract

We consider the properties of a gas of bosonic diatomic molecules in the limit when few of the molecules are dissociated. Taking into account the effects of dissociation and scattering among molecules and atoms, we calculate the dispersion relation for a molecule, and the thermal depletion of the condensate. We calculate the dependence of the Bose-Einstein-condensation (BEC) temperature of a uniform gas on the atom-atom scattering length, and conclude that, for a broad Feshbach resonance, the condensation temperature increases as the molecular state becomes less strongly bound, thereby giving rise to a maximum in the transition temperature in the BEC-BCS crossover. We also argue on general grounds that, for a gas in a harmonic trap and for a narrow Feshbach resonance, the condensation temperature will decrease with increasing scattering length.

Authors:
; ;  [1];  [2];  [3]
  1. Department of Physics, Nanoscience Center, University of Jyvaeskylae, P. O. Box 35, FI-40014 Jyvaeskylae (Finland)
  2. (Finland)
  3. (Denmark)
Publication Date:
OSTI Identifier:
20982375
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.033606; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ATOM-ATOM COLLISIONS; ATOMS; BCS THEORY; BOSE-EINSTEIN CONDENSATION; CONDENSATES; DISPERSION RELATIONS; DISSOCIATION; ELECTRIC GROUNDS; MOLECULES; RESONANCE; SCATTERING; SCATTERING LENGTHS; TRANSITION TEMPERATURE; TRAPS

Citation Formats

Jensen, L. M., Maekelae, H., Pethick, C. J., Department of Physics, University of Turku, FI-20014 Turku, and Nordita, Blegdamsvej 17, DK-2100 Copenhagen O. Bose-Einstein-condensation temperature of a gas of weakly dissociated diatomic molecules. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.033606.
Jensen, L. M., Maekelae, H., Pethick, C. J., Department of Physics, University of Turku, FI-20014 Turku, & Nordita, Blegdamsvej 17, DK-2100 Copenhagen O. Bose-Einstein-condensation temperature of a gas of weakly dissociated diatomic molecules. United States. doi:10.1103/PHYSREVA.75.033606.
Jensen, L. M., Maekelae, H., Pethick, C. J., Department of Physics, University of Turku, FI-20014 Turku, and Nordita, Blegdamsvej 17, DK-2100 Copenhagen O. Thu . "Bose-Einstein-condensation temperature of a gas of weakly dissociated diatomic molecules". United States. doi:10.1103/PHYSREVA.75.033606.
@article{osti_20982375,
title = {Bose-Einstein-condensation temperature of a gas of weakly dissociated diatomic molecules},
author = {Jensen, L. M. and Maekelae, H. and Pethick, C. J. and Department of Physics, University of Turku, FI-20014 Turku and Nordita, Blegdamsvej 17, DK-2100 Copenhagen O},
abstractNote = {We consider the properties of a gas of bosonic diatomic molecules in the limit when few of the molecules are dissociated. Taking into account the effects of dissociation and scattering among molecules and atoms, we calculate the dispersion relation for a molecule, and the thermal depletion of the condensate. We calculate the dependence of the Bose-Einstein-condensation (BEC) temperature of a uniform gas on the atom-atom scattering length, and conclude that, for a broad Feshbach resonance, the condensation temperature increases as the molecular state becomes less strongly bound, thereby giving rise to a maximum in the transition temperature in the BEC-BCS crossover. We also argue on general grounds that, for a gas in a harmonic trap and for a narrow Feshbach resonance, the condensation temperature will decrease with increasing scattering length.},
doi = {10.1103/PHYSREVA.75.033606},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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