Measurement of light shift ratios with a single trapped p138sBap+s ion, and prospects for a parity violation experiment

Thesis (Ph. D.)--University of Washington, 2003This thesis describes the development and implementation of a new scheme for observing RF transitions between spin states in a single, trapped Ba + ion. We use optical pumping to place the ion in a selected magnetic sublevel of either the 6S1/2 ground state or the 5D3/2 metastable state. The ion is exposed to an RF field, and a spin-sensitive version of the electron shelving method detects the resulting spin state. The precision of this kind of RF spectroscopy is limited only by magnetic-field noise, and with the current apparatus, line widths of about 10 Hz can be achieved.This scheme is applied to a precision measurement of light shifts (or AC Stark shifts) in Ba+. Zeeman energies are altered by a circularly-polarized, off resonant laser, and the resulting resonance shifts are measured simultaneously in both the 6S1/2 and 5D3/2 state. When taking the ratio, light intensity and polarization drop out, and we can determine the ratio of P-D to S-P matrix elements with a precision of