Van der Waals-Zeeman Colloquium

Tuesday, 29 May 2007, 16:00h

Ultracold 40K/87Rb Mixtures

Dr. Kai Bongs
Institut für Laser-Physik, Universität Hamburg

I will present recent experiments on quantum degenerate mixtures of bosonic rubidium and fermionic potassium atoms, which connect the field of ultracold quantum gases with condensed matter physics and ultracold chemistry. In particular I will discuss physics of the mixture in an optical lattice, where fermionic impurities significantly influence the bosonic coherence. The origin of this surprisingly strong effect are still under discussion and might connect to disorder or polaron physics. As a further main point I will present the first creation of ultracold heteronuclear molecules in an optical lattice and discuss their binding energies in dependence of an external magnetic field tuned around a Feshbach resonance.