Elastic and inelastic collisions of6Liatoms in magnetic and optical traps

Abstract

We use a full coupled-channels method to calculate collisional properties of magnetically or optically trapped ultracold ${}^6\mathrm{Li}.$ The magnetic-field dependence of the $s$-wave scattering lengths of several mixtures of hyperfine states are determined, as are the decay rates due to exchange collisions. In one case, we find Feshbach resonances at $B=0.08\mathrm{}\mathrm{T}$ and $B=1.98\mathrm{}\mathrm{T}.$ We show that the exact coupled-channels calculation is well approximated over the entire range of magnetic fields by a simple analytical calculation.