arXiv:cond-mat/0210677 · Physical Review A

Expansion of a dipolar condensate

S. Yi, Li You

Published Apr 17, 2003• 33 citations

Abstract

We discuss the expansion of an initially trapped dipolar condensate. When the nominal isotropic s-wave interaction strength becomes tunable through a Feshbach resonance, anisotropic dipolar effects are shown to be detectable under current experimental conditions [E. A. Donley et al., Nature London 412, 295 (2001)].

DOI: 10.1103/physreva.67.045601

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arXiv:cond-mat/0210677 · Physical Review A

Expansion of a dipolar condensate

S. Yi, Li You

Published Apr 17, 2003• 33 citations

arXiv HTML PDF

Abstract

DOI: 10.1103/physreva.67.045601

Related papers

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{}^{85}\mathrm{Rb}

atoms), anisotropic dipolar effects are shown to be detectable under current experimental conditions [E. A. Donley et al., Nature (London) 412, 295 (2001)].

6 μ_{\rm B}

) magnetic moments of Chromium atoms. Several dramatic effects of the dipolar interaction are observed: the usual inversion of ellipticity of the condensate during time-of flight is inhibited, the stability of the dipolar gas depends strongly on the trap geometry, and the explosion following the collapse of an unstable dipolar condensate displays d-wave like features.

The

s

-wave interaction is usually the dominant form of interactions in atomic Bose-Einstein condensates (BECs). Recently, Feshbach resonances have been employed to reduce the strength of the

s

-wave interaction in many atomic species. This opens the possibilities to study magnetic dipole-dipole interactions (MDDIs) in BECs, where the novel physics resulting from long-range and anisotropic dipolar interactions can be explored. Using a variational method, we study the effect of MDDIs on the statics and dynamics of atomic BECs with tunable

s

-wave interactions for a variety of species, including both nonalkali metals with large magnetic dipole moments (

{}^{52}

Cr,

{}^{164}

Dy,

{}^{168}

Er) and alkali metals (with much smaller magnetic dipole moments). A parameter of magnetic Feshbach resonances, ${\ensuremath{\epsilon}}_{dd,\text{max}}$, is used to quantitatively indicate the feasibility of experimentally observing MDDI effects in different atomic species. We find that strong MDDI effects should be observable in both in-trap and time-of-flight behaviors, not only for the strongly magnetic dipolar species but also for the alkali-metal BECs of

{}^{7}

Li,

{}^{39}

K, and

{}^{133}

Cs. In addition, we predict several effects which should be experimentally observable. Our results provide a helpful guide for experimentalists to realize and study atomic dipolar quantum gases.