Interacting Feshbach Molecules

Niels Syassen

Published Jan 1, 2008• 1 citation

Abstract

This thesis reports on experiments with ultracold atomic and molecular quantum gases. Magnetically tunable Feshbach resonances are used to associate diatomic molecules from atomic 87Rb in a three-dimensional optical lattice. In a first experiment, molecules are formed by a sudden jump of the magnetic field to the resonance. This induces coherent atom-molecule oscillations with large amplitude. In another experiment, a dissipative analog of the one-dimensional Tonks-Girardeau gas is realized with molecules in an optical lattice. Inelastic collisions between the molecules lead to particle loss. This interaction is so strong that the system reaches the strongly correlated regime, and the molecules, which are bosons, are forced to behave much like fermions. The strong correlations suppress the molecule loss rate by up to three orders of magnitude.

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