title: Ionization studies in laser-excited alkaline-earth vapors.
abstract: We report on the time behavior of ionization signals produced by laser excitation of Ca and Ba atomic vapor to high-Rydberg states. A space-charge-limited thermionic diode detector shows a long-lived (>I-msec) ionization signal. However, optical detection of atomic ions (Ca+, Ba+) shows that these species live for much shorter times (<100 microsec). These results, in conjunction with published results on mass-spectrometric studies of high-density atomic beams, suggest that our ionization signal is primarily due to molecular species (Ca2+, Ba2+). We also observed optically pumped amplified spontaneous emission and stimulated electronic Raman scattering in Ca+ and Ba+.
authors.affiliation: IBD Thomas J. Watson Research Center, PO Box 218, Yorktown Heights, New York 10598, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Hermann
authors.forename: J J
authors.initials: JJ
authors.lastname: Wynne