Laser action in singly ionized krypton and xenon

Laser oscillation has been observed in pulsed krypton and xenon discharges on 21 wavelengths spanning the visible portion of the spectrum. All lines observed arise from transitions between levels of the singly-ionized state of the atoms (KrII, XeII spectra). The wavelengths and tentative level assignments are given in Table I for krypton and Table II for xenon. Oscillation between energy levels of ions has previously been reported for mercury 1 and argon 2. The levels reported here are analogous to those observed in argon. The xenon transitions are all s → p or s’ → p’, while the krypton transitions are predominantly of this type, but include one p → d two p’ → d.