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 (>1-msec) ionization signal. However, optical detection of atomic ions (Ca+, Ba+) shows that these species live for much shorter times (<100 μsec). 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+.
© 1980 Optical Society of America
Original Manuscript: February 1, 1980
Published: June 1, 1980
J. P. Hermann and J. J. Wynne, "Ionization studies in laser-excited alkaline-earth vapors," Opt. Lett. 5, 236-238 (1980)