Few-body collisions in a quantum gas mixture of 40K and 87Rb atoms

<p>This thesis describes experiments on few-body interactions in a mixture of ultracold bosonic\&nbsp;<span style="line-height: 1.6em;">⁸⁷Rb and fermionic ⁴⁰K atoms. Ultracold atoms are celebrated as a platform to explore fundamental\&nbsp;</span><span style="line-height: 1.6em;">quantum physics because their internal states, external potentials, and interactions with each other\&nbsp;</span><span style="line-height: 1.6em;">can be controlled by straightforward electrical and optical tools. In the case of Bose-Fermi mixtures,\&nbsp;</span><span style="line-height: 1.6em;">control comes at the cost of stability when strong interactions give rise to inelastic collisions that\&nbsp;</span><span style="line-height: 1.6em;">destroy the atomic samples. I present detailed measurements of the cross sections for these inelastic\&nbsp;</span><span style="line-height: 1.6em;">processes and discuss how they fit into an emerging pattern of resonances that is leading to better\&nbsp;</span><span style="line-height: 1.6em;">models of few-atom interactions. These phenomena have their roots in universal Emov physics,\&nbsp;</span><span style="line-height: 1.6em;">which is a paradigm of quantum three-body interactions that was originally inspired by exotic\&nbsp;</span><span style="line-height: 1.6em;">nuclear states. I also discuss several methods to control the formation of KRb Feshbach molecules\&nbsp;</span><span style="line-height: 1.6em;">within the finite lifetime of the interacting K and Rb atomic mixture.</span></p>