Spectroscopic Determination of thes-Wave Scattering Length of Lithium

Superfluidity of Spin-Polarized6Li

“…A better estimate of the scattering length can be obtained by repeating the experiment of Ref. [7] for 6 Li. In regards to the properties of the condensed phase, it is well known from liquid 3 He that the phase below the critical temperature is truly superfluid, because it costs a finite amount of free energy to have gradients in the phase of the order parameter D 0 .…”

“…Therefore, magnetically trapped 6 Li promises to be an ideal system to study degeneracy effects in a weakly interacting Fermi gas, thus providing valuable complementary information on the workings of quantum mechanics at the macroscopic level. Moreover, using a combination of theoretical analysis and experimental results [5][6][7], accurate knowledge of the interparticle (singlet and triplet) potential curves of lithium have recently been obtained, which lead to the prediction of a large and negative s-wave scattering length a of 24.6 3 10 3 a 0 (a 0 is the Bohr radius) for a spin-polarized 6 Li gas. This is important for two reasons: First, the fact that the scattering length is negative implies that at the low temperatures of interest [L ¿ r V , where L ͑2ph 2 ͞mk B T͒ 1͞2 is the thermal de Broglie wavelength of the atoms and r V is the range of the interaction] the effective interaction between the lithium atoms is attractive, and we expect a BCS-like phase transition to a superfluid state at a critical temperature…”

Photoassociation of a Bose-Einstein Condensate near a Feshbach Resonance

“…Future studies should explore the dynamical behavior of loss since K p is expected to be time dependent in the dissociation regime [3,[5][6][7]. Finally, Feshbach enhanced PA may prove useful in realizing the long-sought goal of coherent oscillation between atomic and molecular condensates [26] or for efficient production of ground-state molecules [27] using a twophoton process [28], similar to recent experiments that have shown that the rate of two-photon processes can be greatly enhanced by first magnetoassociating the atoms by sweeping through a FR [29].…”

Formation of fermionic molecules via interisotope Feshbach resonances

“…Here we want to combine all available cold collision data on lithium, and we add the positions of three p-wave Feshbach resonances, which have been measured recently [25], and experimental data of 7 Li [3,26], to the set of experiments. In this combined isotope analysis we perform a mass scaling procedure for the triplet boundary condition only.…”