5 research outputs found
Ultracold heteronuclear molecules in a 3D optical lattice
We report on the creation of ultracold heteronuclear molecules assembled from
fermionic 40K and bosonic 87Rb atoms in a 3D optical lattice. Molecules are
produced at a heteronuclear Feshbach resonance both on the attractive and the
repulsive side of the resonance. We precisely determine the binding energy of
the heteronuclear molecules from rf spectroscopy across the Feshbach resonance.
We characterize the lifetime of the molecular sample as a function of magnetic
field and measure between 20 and 120ms. The efficiency of molecule creation via
rf association is measured and is found to decrease as expected for more deeply
bound molecules.Comment: 4 pages, 4 figure
Analysis of Localization Phenomena in Weakly Interacting Disordered Lattice Gases
Disorder plays a crucial role in many systems particularly in solid state
physics. However, the disorder in a particular system can usually not be chosen
or controlled. We show that the unique control available for ultracold atomic
gases may be used for the production and observation of disordered quantum
degenerate gases. A detailed analysis of localization effects for two possible
realizations of a disordered potential is presented. In a theoretical analysis
clear localization effects are observed when a superlattice is used to provide
a quasiperiodic disorder. The effects of localization are analyzed by
investigating the superfluid fraction and the localization length within the
system. The theoretical analysis in this paper paves a clear path for the
future observation of Anderson-like localization in disordered quantum gases.Comment: 9 pages, 13 figure