Measurement of the probabilities of forbidden radiative transitions in the barium atom

Roy H. Garstang

H. Gabstang

S. P. Goreslavskiǐ, Nikolai B. Delone, В. П. Крайнов

David G. Sarkisyan, S O Sapondzhyan

Emission at wavelengths of 1.0615 and 1.074 μ from a self-mode-locked YAG:Nd3+ laser was observed at thresholds which were only 1.5 and 3.5 times higher than the threshold for the emission of radiation with λ = 1.064 μ. Efficient conversion (characterized by a quantum efficiency of ~ 15%) of the third harmonics of the radiations with λ = 1.064 and 1.0615 μ to the visible (590 nm) and ultraviolet (250 nm) ranges was achieved in atomic barium vapor. Electron stimulated Raman scattering due to a strongly forbidden transition in a system of Ba atoms was observed for the first time.

V S Verkhovskiĭ, Vladimir M. Klimkin, В. Е. Прокопьев +3 more

An experimental investigation was made of stimulated Raman scattering (STRS) of excimer laser radiation in barium, thulium, and europium vapors. The energy of XeF* laser radiation ( λ = 351 nm) converted to the yellow range (585 nm) in barium vapor was 6 mJ and the conversion efficiency was ∼39%. The spectral composition of the converted radiation is governed by the STRS, by four-wave parametric processes, and also by lasing due to the natural barium transition. Selection of the pump frequencies is required to concentrate the converted radiation at a single frequency and to reduce its divergence. Stimulated Raman scattering of XeCl* laser radiation ( λ = 308 nm) was achieved in thulium vapor at λ = 422 nm. In europium vapor in quasiresonance with the 6 s 2 8 S 0 1/2 –5 d 2 10 P 0 11/2 forbidden transition, stimulated emission was obtained due to the natural 5 d 2 10 P 0 11/2 –6 s 6 p 10 P 11/2 and 5 d 2 10 P 0 11/2 –6 s 6 p 10 P 3/2 transitions.

Thomas R. O’Brian