Dual-species quantum degeneracy of potassium-40 and rubidium-87 on an   atom chip
  In this article we review our recent experiments with a 40K-87Rb mixture. We demonstrate rapid sympathetic cooling of a 40K-87Rb mixture to dual quantum degeneracy on an atom chip. We also provide details on efficient BEC production, species-selective magnetic confinement, and progress toward integration of an optical lattice with an atom chip. The efficiency of our evaporation allows us to reach dual degeneracy after just 6 s of evaporation - more rapidly than in conventional magnetic traps. When optimizing evaporative cooling for efficient evaporation of 87Rb alone we achieve BEC after just 4 s of evaporation and an 8 s total cycle time. 
M. H. T. Extavour, L. J. LeBlanc, T. Schumm, B. Cieslak, S. Myrskog,   A. Stummer, S. Aubin, J. H. Thywissen