Exploring an ultracold fermi-fermi mixture: Interspecies Feshbach resonances and scattering properties of Li-6 and K-40

We report on the observation of Feshbach resonances in an ultracold mixture of two fermionic species, Li-6 and K-40. The experimental data are interpreted using a simple asymptotic bound state model and full coupled channels calculations. This unambiguously assigns the observed resonances in terms of various s- and p-wave molecular states and fully characterizes the ground-state scattering properties in any combination of spin states.