The Efimov effect in lithium 6

We analyse the recent experiments investigating the low-energy physics of three lithium 6 atoms in different internal states with resonant two-body scattering lengths. All observed features are qualitatively consistent with the expected Efimov effect, i.e. the effective universal three-body attraction that arises for large values of the scattering lengths. However, we find that a quantitative description at negative energy requires non-universal two- and three-body corrections due to presently unknown behaviour at short distance. An attempt to implement these corrections is made through energy-dependent parameters fitted to the experimental data.Comment: 12 pages, 8 figures. Same as published version. Contains additions detailing the derivation of some formulae; http://dx.doi.org/10.1016/j.crhy.2010.12.00

Optical Feshbach resonances of Alkaline-Earth atoms in a 1D or 2D optical lattice

Motivated by a recent experiment by Zelevinsky et al. [Phys. Rev. Lett. 96, 203201], we present the theory for photoassociation and optical Feshbach resonances of atoms confined in a tight one-dimensional (1D) or two-dimensional (2D) optical lattice. In the case of an alkaline-earth intercombination resonance, the narrow natural width of the line makes it possible to observe clear manifestations of the dimensionality, as well as some sensitivity to the scattering length of the atoms. Among possible applications, a 2D lattice may be used to increase the spectroscopic resolution by about one order of magnitude. Furthermore, a 1D lattice induces a shift which provides a new way of determining the strength of a resonance by spectroscopic measurements.Comment: 12 pages, 4 figures. Typos were corrected and a connection was made to the fermionization of boson