Physical Review Letters
Electric Field Ionization of High Rydberg States of Ar with Sequences of Identical Pulses
Frédéric Merkt, R. J. Rednall, Stuart R. Mackenzie, T. P. Softley
Abstract
Novel field-ionization behavior of very high Rydberg states of Ar ( $n\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}50--250$) is observed using sequential pulsed electric fields. Fast autoionization acts as a filter against adiabatic field ionization near the ${}^{2}{P}_{1/2}$ threshold, whereas both diabatic and adiabatic field ionization occur near the ${}^{2}{P}_{3/2}$ threshold. Sequences of up to 9 equivalent pulses yield recurrent field ionization signals near the ${}^{2}{P}_{3/2}$ threshold, provided that the field returns close to zero between pulses, demonstrating a statistical redistribution of the Rydberg population amongst all states of a given Stark manifold near zero field.