Ionization of Rydberg Atoms at Patterned Electrode Arrays
Dunning, F. B.
Doctor of Philosophy
The present work explores the effect of controlled surface fields on the ionization of Rydberg atoms near surfaces. Lithographically-patterned micrometer scale electrode arrays are used to generate controlled surface electric fields. The data show that application of even small electrode biases (~±1V) can lead to a transition from ionization of the incident atoms by short-range tunneling to field ionization well above the target surface. The resulting ions are efficiently detected using ion collection fields whose strengths are substantially smaller than those required for direct field ionization implying the application of surface ionization in the detection of low-n Rydberg atoms. The data are analyzed with the aid of a Monte Carlo model and further demonstrate the critical role that local surface fields can play in governing the nature of atom-surface interactions.