Radiofrequency Ac Zeeman Trapping For Neutral Atoms
Rotunno, Andrew Peter
Rotunno, Andrew Peter
Abstract
This thesis presents the first experimental demonstration of a two-wire AC Zeeman trap on an atom chip. The AC Zeeman energy is a resonant, bipolar, state-dependent atomic energy shift produced by alternating magnetic fields with frequencies near hyperfine transitions. We demonstrate that high gradients in this energy, as near an atom chip, can produce a spin-state selective force greater than gravity for ultracold rubidium atoms. Our novel trap is generated by a local minimum in AC Zeeman energy. Using less than one watt of power, we demonstrate trap frequency on the order of a few hundred Hz, trap depth about 5 μK, and quarter-second lifetimes. Motivated by trapped atom interferometry, this proof of principle AC Zeeman trap can also augment atom and ion experiments as a dynamic spin-dependent potential. Different parameters in the current arrangement can produce regions of linear gradient, flat saddle points, square- and donut-shaped traps, offering a new set of tools for atom chip experiments. This thesis also presents the relevant dressed atomic theory, four AC Zeeman trap designs, Rabi frequency measurements, numerical trap simulations, and the AC skin effect in wide rectangular wires.
Description
Date
2021-01-01