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Title: Dipole-dipole instability of atom clouds in a far-detuned optical dipole trap

Abstract

The effect of the dipole-dipole interaction on the far-off-resonance optical dipole trapping scheme is calculated by a mean-field approach. The trapping laser field polarizes the atoms and the accompanying dipole-dipole energy shift deepens the attractive potential minimum in a pancake-shaped cloud. At high density the thermal motion cannot stabilize the gas against self-contraction and an instability occurs. We calculate the boundary of the stable and unstable equilibrium regions on a two-dimensional phase diagram of the atom number and the ratio of the trap depth to the temperature. We discuss the limitations imposed by the dipole-dipole instability on the parameters needed to reach Bose-Einstein condensation in an optical dipole trap.

Authors:
;  [1]
  1. Research Institute of Solid State Physics and Optics, Hungarian Academy of Sciences, H-1525 Budapest P.O. Box 49 (Hungary)
Publication Date:
OSTI Identifier:
20982558
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.053416; (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; ATOMS; BOSE-EINSTEIN CONDENSATION; COMPUTER CALCULATIONS; DENSITY; DIPOLES; INSTABILITY; INTERACTIONS; LASER RADIATION; MEAN-FIELD THEORY; PHASE DIAGRAMS; PHOTON-ATOM COLLISIONS; POTENTIALS; RADIATION PRESSURE; RESONANCE; TRAPPING; TRAPS; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Nagy, D., and Domokos, P.. Dipole-dipole instability of atom clouds in a far-detuned optical dipole trap. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.053416.
Nagy, D., & Domokos, P.. Dipole-dipole instability of atom clouds in a far-detuned optical dipole trap. United States. doi:10.1103/PHYSREVA.75.053416.
Nagy, D., and Domokos, P.. Tue . "Dipole-dipole instability of atom clouds in a far-detuned optical dipole trap". United States. doi:10.1103/PHYSREVA.75.053416.
@article{osti_20982558,
title = {Dipole-dipole instability of atom clouds in a far-detuned optical dipole trap},
author = {Nagy, D. and Domokos, P.},
abstractNote = {The effect of the dipole-dipole interaction on the far-off-resonance optical dipole trapping scheme is calculated by a mean-field approach. The trapping laser field polarizes the atoms and the accompanying dipole-dipole energy shift deepens the attractive potential minimum in a pancake-shaped cloud. At high density the thermal motion cannot stabilize the gas against self-contraction and an instability occurs. We calculate the boundary of the stable and unstable equilibrium regions on a two-dimensional phase diagram of the atom number and the ratio of the trap depth to the temperature. We discuss the limitations imposed by the dipole-dipole instability on the parameters needed to reach Bose-Einstein condensation in an optical dipole trap.},
doi = {10.1103/PHYSREVA.75.053416},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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