Bosonic and fermionic atoms in optical lattices

Miguel A. Cazalilla, Andrew Fu Wah Ho, Thierry Giamarchi

Sebastian Will, Thorsten Best, Simon G. Braun +3 more

Sebastian Will

Xavier Baillard, Mathilde Fouché, Rodolphe Le Targat +14 more

We report recent experiments performed with our Sr optical lattice clock. With the fermionic isotope87Sr, the clock accuracy approaches 10-15using spin-polarized atoms. We also report the first accuracy evaluation of an optical lattice clock with bosonic atoms, here88Sr.

Michael Köhl, Henning Moritz, Thilo Stöferle +2 more

Kenneth Günter, Thilo Stöferle, Henning Moritz +2 more

We have studied mixtures of fermionic (40)K and bosonic (87)Rb quantum gases in a three-dimensional optical lattice. We observe that an increasing admixture of the fermionic species diminishes the phase coherence of the bosonic atoms as measured by studying both the visibility of the matter wave interference pattern and the coherence length of the bosons. Moreover, we find that the attractive interactions between bosons and fermions lead to an increase of the boson density in the lattice which we measure by studying three-body recombination in the lattice. In our data, we do not observe three-body loss of the fermionic atoms. An analysis of the thermodynamics of a noninteracting Bose-Fermi mixture in the lattice suggests a mechanism for sympathetic cooling of the fermions in the lattice.