Invited Speakers

Joseph Thywissen jht@physics.utoronto.ca University of Toronto

Bose and Fermi gases in single- and double-well chip traps We describe our recent experiments with 40K, a fermion, and 87Rb, a boson, in the quantum degenerate regime. First, we describe our apparatus, which is based on a microfabricated magnetic trap. These "chip" traps provide strong magnetic field gradients, which compress the clouds and allow for evaporative and rapid sympathetic cooling. Next, we will discuss our path to dual quantum degeneracy in this system. Finally, we will discuss the use of RF adiabatic potentials in the chip trap, to split degenerate clouds. First-order coherence can be observed by looking at fringe contrast and repeatability. Second-order coherence can be measured using counting statistics. We will discuss our first measurements of both of these quantities, and improvements required to observe for quantum statistics of fermions in the double well system. Note there are several connections between "UofT" and "UT": first, the Ramsauer-Townsend effect we observe at UofT in the 40K-87Rb collision cross-section was also observed in the 85Rb experiments at UT; also, the mean-field-induced suppression of shot noise in 87Rb atom number observed at UT for a single well, may be observable in the atom number difference statistics, in our double well system.