Production of quantum degenerate mixtures of ytterbium and lithium with   controllable inter-species overlap
  Quantum degenerate mixtures of alkali and spin-singlet atoms form the starting point for studying few- and many-body physics of mass-imbalanced pairs as well as the production of paramagnetic polar molecules. We recently reported the achievement of dual-species quantum degeneracy of a mixture of lithium and ytterbium atoms. Here we present details of the key experimental steps for the all-optical preparation of these mixtures. Further we demonstrate the use of the magnetic field gradient tool to compensate for the differential gravitational sag of the two species and control their spatial overlap. 
Anders H. Hansen, Alexander Y. Khramov, William H. Dowd, Alan O.   Jamison, Benjamin Plotkin-Swing, Richard J. Roy, and Subh...
cond-mat.quant-gas physics.atom-ph