Role of interactions in 87Rb-40K Bose-Fermi mixtures in a 3D optical lattice.
We investigate the effect of interspecies interaction on a degenerate mixture of bosonic 87Rb and fermionic 40K atoms in a three-dimensional optical lattice potential. Using a Feshbach resonance, the 87Rb-40K interaction is tuned over a wide range. Through an analysis of the 87Rb momentum distribution, we find a pronounced asymmetry between strong repulsion and strong attraction. In the latter case, we observe a marked shift in the superfluid to Mott insulator transition, which we attribute to a renormalization of the Bose-Hubbard parameters due to self-trapping.
Best
Th
T
Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudinger Weg 7, 55128 Mainz, Germany.
Will
S
S
Schneider
U
U
Hackermüller
L
L
van Oosten
D
D
Bloch
I
I
Lühmann
D-S
DS