Atom Trapping and Spectroscopy in Cavity-Generated Optical Potentials.

Abstract

In this thesis I study atom trapping in GHz-deep optical lattices, generated by an in-vacuum near-concentric optical cavity at 1064~nm, to perform experiments on cold Rydberg atoms. In contemporary atomic physics, cold Rydberg atoms are widely used due to their high sensitivity to static and ac fields, as well as to their unusual collision properties. In my research, I intend to study the response of such atoms to GHz-deep optical traps. In the atom preparation procedure, the deep optical-lattice trap adiabatically compresses the cold rubidium atom sample within the lattice wells, where the atoms experience light shifts of several GHz. The deep optical-lattice trap allows me to perform several spectroscopy experiments which have not yet been done. An experimental challenge that had to be overcome was the realization of GHz-deep light shift traps (which are highly unusual in the field). The design of the cavity experiment also allows a fast experimental repetition rate (which is advantageous in spectroscopy experiments), a large atomic number density, and cold-atom samples with a highly elongated aspect ratio.

A near-concentric cavity is the only type of stable two-mirror cavity that has a focus at the cavity center. This configuration not only provides high laser intensity at the cavity center, but also nearly perfect three-dimensional optical trapping potential based on the cavity's non-degenerate cavity modes. The cavity-generated optical trapping potentials offer a platform for deep ponderomotive Rydberg spectroscopy which would be otherwise very difficult in a conventional optical-lattice experimental setup.