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Title: Optimized production of large Bose-Einstein condensates

Abstract

We describe several routes to quantum degenerate gases based on simple schemes to efficiently load atoms into and evaporate them from a 'dimple' crossed dipolar trap. The dimple is loaded nonadiabatically by collisions between atoms which are trapped in a reservoir which can be provided either by a dark spontaneous-force magneto-optical trap (MOT), the (aberrated) laser beam itself, or by a quadrupolar or quadratic magnetic trap. Optimal loading parameters for the dimple, relatively high temperature, and tight optical trap are derived from thermodynamic equations including possible inelastic and Majorana losses. Evaporative cooling is described by a set of simple equations, taking into account gravity, the possible occurrence of the hydrodynamical regime, Feshbach resonances, and three body recombination. The solution implies that to have efficient evaporation the elastic collisional rate (in s{sup -1}) must be on the order of the trap frequency and lower than 100 times the temperature in microkelvins. Following this approach Bose-Einstein condensates with more than 10{sup 7} atoms should be obtained in much less than 1 s starting from an ordinary MOT setup.

Authors:
; ; ; ;  [1];  [2]
  1. Laboratoire Aime Cotton, CNRS II, Batiment 505, Campus d'Orsay, 91405 Orsay Cedex (France)
  2. Laboratoire de Physique des Lasers, UMR 7538 CNRS, Universite de Paris 13, 99 Avenue J.-B. Clement, 93430 Villetaneuse (France)
Publication Date:
OSTI Identifier:
20787128
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.73.043410; (c) 2006 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; ENERGY LOSSES; EVAPORATION; EVAPORATIVE COOLING; GASES; GRAVITATION; HYDRODYNAMICS; LASER RADIATION; MAGNETO-OPTICAL EFFECTS; PHOTON-ATOM COLLISIONS; RADIATION PRESSURE; RECOMBINATION; RESONANCE; THREE-BODY PROBLEM; TRAPPING; TRAPS

Citation Formats

Comparat, D., Fioretti, A., Stern, G., Dimova, E., Pillet, P., and Tolra, B. Laburthe. Optimized production of large Bose-Einstein condensates. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Comparat, D., Fioretti, A., Stern, G., Dimova, E., Pillet, P., & Tolra, B. Laburthe. Optimized production of large Bose-Einstein condensates. United States. doi:10.1103/PHYSREVA.73.0.
Comparat, D., Fioretti, A., Stern, G., Dimova, E., Pillet, P., and Tolra, B. Laburthe. Sat . "Optimized production of large Bose-Einstein condensates". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20787128,
title = {Optimized production of large Bose-Einstein condensates},
author = {Comparat, D. and Fioretti, A. and Stern, G. and Dimova, E. and Pillet, P. and Tolra, B. Laburthe},
abstractNote = {We describe several routes to quantum degenerate gases based on simple schemes to efficiently load atoms into and evaporate them from a 'dimple' crossed dipolar trap. The dimple is loaded nonadiabatically by collisions between atoms which are trapped in a reservoir which can be provided either by a dark spontaneous-force magneto-optical trap (MOT), the (aberrated) laser beam itself, or by a quadrupolar or quadratic magnetic trap. Optimal loading parameters for the dimple, relatively high temperature, and tight optical trap are derived from thermodynamic equations including possible inelastic and Majorana losses. Evaporative cooling is described by a set of simple equations, taking into account gravity, the possible occurrence of the hydrodynamical regime, Feshbach resonances, and three body recombination. The solution implies that to have efficient evaporation the elastic collisional rate (in s{sup -1}) must be on the order of the trap frequency and lower than 100 times the temperature in microkelvins. Following this approach Bose-Einstein condensates with more than 10{sup 7} atoms should be obtained in much less than 1 s starting from an ordinary MOT setup.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 4,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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