Demonstration of dense mesoscopic atomic samples in a holographic atom trap.

摘要

This dissertation describes experiments involving the Holographic Atom Trap (HAT). The HAT is a novel far-off resonant optical trap formed by the interference of five Nd:YAG laser beams. At the intersection of the five beams a lattice of microtraps is formed. Three primary experiments will be discussed. The purpose of this work is the development of high density, mesoscopic atomic samples for use in studying Rydberg physics.; The first experiment described in this dissertation uses the HAT to attain high phase space densities. The phase space density is increased by performing forced evaporation in the HAT. A model has been developed to understand the evaporation dynamics. Using the model as a guide for how to efficiently lower the trap depth, we have increased the phase space density by a factor of 200 resulting in phase space densities in excess of 1.1.; The second experiment uses the HAT to attain high density atomic samples. Atoms are evaporated from the HAT until the phase space density approaches unity. Then the trap depth is rapidly increased to compress the atom cloud. The result is atomic densities in excess of 1 x 1015 atoms/cm3, the highest atom densities attained in incoherent ultracold matter. We have verified these densities three ways: measuring the number of atoms, the temperature, and the oscillation frequency of the atoms in the cloud; measuring the 3-body recombination rate; and measuring the spatial profile of the dense atomic clouds. We have used the same method to produce mesoscopic atom samples which contain 2000 atoms and are 5.6 mum in the longest direction. Creation of these samples represents an important step towards the first observation of a complete dipole blockade and eventually the realization of using Rydberg atoms for quantum computation.; The final experiment described in this dissertation is a prelude to the Rydberg experiments in the HAT: the creation of 46d and 48s Rydberg atoms in a Magneto-optical trap (MOT), and the investigation of suppression of Rydberg excitation from Rydberg-Rydberg interactions. This work is the first demonstration of a two photon excitation of Rydberg atoms in a MOT.