UC Riverside

In this dissertation we proposed and modeled five ultra cold atoms experiments that make use of quantum effects to produce novel macroscopic phenomena. The first of these experiments is a proposal to produce a p-wave superfluid using two different atomic species.

The pairing species is trapped in two-dimensions and the other species is allowed to move in three-dimensions and mediates the p-wave pairing interaction. We confirm our predictions using the functional Renormalization Group method.

The next experiment studies how macroscopic cat states can be produced and detected in bosonic interferometers. A bosonic interferometer is composed of ultra-cold bosons that can condense in one of two modes. Tunneling and interactions are the primary contributions to the dynamics and in cooperation can produce highly entangled states such as Schrodinger cat states. We show how the quantum Fisher information, a tool in quantum metrology, can be used to perform a partial state tomography to determine the nature of the superposition in experimental cat states.

In the last three proposals, we study the long time equilibration dynamics of three different proposed experiments. The first proposed experiment takes place in the same bosonic interferometer as discussed in the Schr{\"o}dinger cat work, and we identify a novel mechanism for the breakdown of thermalization with the slow dynamics of an unstable fixed point in a semi-classical approximation. The second proposed experiment also takes place in the same bosonic model, but involves a periodic kick to the interaction strength. We find that these dynamics can produce a time-crystal-like state where discrete time-translation symmetry is broken in the long time dynamics. Finally, we study the long time dynamics of a clean fermionic chain and a disordered fermionic chain that are coupled by density density interactions. In this proposal, we find that the effects of disorder can be transferred to the clean chain and prevent thermalization.