Understanding the production of dual Bose-Einstein condensation with sympathetic cooling

Delannoy, Guillaume; Murdoch, Stuart G.; Boyer, Vincent; Josse, Vincent; Bouyer, Philippe; Aspect, Alain

doi:10.1103/physreva.63.051602

Cited by 65 publications

(92 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the Boltzmann regime, an analytical formula for the evolution of the temperatures in a mixture of equal mass atoms was derived in Ref. [16]. In the same paper, the approach is extended towards atoms with different mass, however, the dependence of the cooling efficiency on the mass ratio is derived under the assumption of equal trap frequencies.…”

Section: Sympathetic Coolingmentioning

confidence: 99%

“…Below, we adapt the approach of Ref. [16] by assuming an explicit trap potential, so that our results remain valid for large mass ratios. The average energy transfer per collision can be calculated from simple kinematics,…”

Section: Sympathetic Coolingmentioning

confidence: 99%

“…For equal mass atoms in a harmonic trap, approximately 3 collisions are needed for thermalization (see [16] and references therein), as the heat capacity per atom is 3k B . For 133 Cs and 7 Li, we need 3/ξ ≈ 15 collisions to thermalize.…”

Section: Sympathetic Coolingmentioning

confidence: 99%

“…To interpret this evaporation and to estimate a collison cross section from it, we adapt a model given in Ref. [16] and we develop a rate equation model for sympathetic cooling with slow evaporation. This paper is organized as follows: An overview of the apparatus is given in section 2 and the methods for loading and characterization of the trap are discussed in section 3.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Mixture of ultracold lithium and cesium atoms in an optical dipole trap

et al. 2001

View full text Add to dashboard Cite

We present the first simultaneous trapping of two different ultracold atomic species in a conservative trap. Lithium and cesium atoms are stored in an optical dipole trap formed by the focus of a CO 2 laser. Techniques for loading both species of atoms are discussed and observations of elastic and inelastic collisions between the two species are presented. A model for sympathetic cooling of two species with strongly different mass in the presence of slow evaporation is developed. From the observed Cs-induced evaporation of Li atoms we estimate a cross section for cold elastic Li-Cs collisions.

show abstract

Section: Sympathetic Coolingmentioning

confidence: 99%

Section: Sympathetic Coolingmentioning

confidence: 99%

Section: Sympathetic Coolingmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Mixture of ultracold lithium and cesium atoms in an optical dipole trap

et al. 2001

View full text Add to dashboard Cite

show abstract

“…The cross-species collision cross section can be extracted from the thermalization speed using the following model [28]. In the case of unequal collision partners about 2.7/ξ collisions per atom are needed for thermalization of a gas, γ thm = ξγ coll /2.7.…”

mentioning

confidence: 99%

Quantum-Degenerate Mixture of Fermionic Lithium and Bosonic Rubidium Gases

et al. 2005

View full text Add to dashboard Cite

We report on the observation of sympathetic cooling of a cloud of fermionic 6 Li atoms which are thermally coupled to evaporatively cooled bosonic 87 Rb. Using this technique we obtain a mixture of quantum-degenerate gases, where the Rb cloud is colder than the critical temperature for BoseEinstein condensation and the Li cloud colder than the Fermi temperature. From measurements of the thermalization velocity we estimate the interspecies s-wave triplet scattering length |as| = 20 +9 −6 aB. We found that the presence of residual rubidium atoms in the |2, 1 and the |1, −1 Zeeman substates gives rise to important losses due to inelastic collisions.PACS numbers: 05.30. Fk, 05.30.Jp, 32.80.Pj, The recent realization of degenerate gases of homonuclear diatomic molecules is an important achievement for the physics of ultracold dilute quantum gases [1,2]. The key to this spectacular success was the use of Feshbach resonances which allow for an adiabatic transformation from free pairs to molecules in the least bound state close to the dissociation energy [3]. The large internal energy makes the gas unstable against collisions between the molecules, which transform the energy into kinetic energy of the collision partners [4]. The very long lifetimes of up to several 10 s observed for dimers made of fermionic 6 Li [2] are explained by the fact that the atoms are only loosely bound with a binding energy of 1 µK such that they still behave very much like individual atoms [5]. Collisions are thus suppressed due to Pauli-blocking. Fermionic lithium is now a very promising candidate for exploring the cross-over regime between the Bardeen-Cooper-Schrieffer (BCS) model for superconductivity based on Cooper pairs and the regime of a Bose-Einstein condensate of composite bosons [6].In contrast to homonuclear dimers molecules made of two different atomic species exhibit a permanent electric dipole moment. The LiRb dimer has a very large permanent electric dipole moment of up to 4.2 Debye [7]. The intermolecular interaction in such a heteronuclear gas has a pronounced long-range character, which fundamentally alters its behavior at low temperatures [8] and brings global properties of the gas into play. The geometric shape of the cloud for instance will influence the total interaction energy and thus the stability of the gas [9].A possible approach to generate a polar molecular gas would use a Feshbach resonance in close analogy to the homonuclear experiments [1,2]. Only recently first heteronuclear Feshbach resonances have been observed [10]. Weakly bound heteronuclear molecules are expected to be relatively stable against collisions if one of the two atoms is a fermion [5]. For such molecules Pauli-blocking is at least partially effective, even though reactive collisions may reduce their lifetime [11]. As an alternative to Feshbach resonances, photoassociation is used to transform atomic pairs into molecules. Photoassociation has been extensively investigated for the homonuclear case [12], and there are already examples of successf...

show abstract

Laser Cooling

Mendonça¹,

Terças

2012

Physics of Ultra-Cold Matter

View full text Add to dashboard Cite

Understanding the production of dual Bose-Einstein condensation with sympathetic cooling

Cited by 65 publications

References 20 publications

Mixture of ultracold lithium and cesium atoms in an optical dipole trap

Mixture of ultracold lithium and cesium atoms in an optical dipole trap

Quantum-Degenerate Mixture of Fermionic Lithium and Bosonic Rubidium Gases

Laser Cooling

Contact Info

Product

Resources

About