Investigation of electronic stimulated Raman scattering of excimer laser radiation by metal atoms

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 6s^{2 8}S ⁰_1/2–5d^{2 10}P⁰_11/2 forbidden transition, stimulated emission was obtained due to the natural 5d^{2 10}P⁰_11/2–6s 6p¹⁰P_11/2 and 5d^{2 10}P⁰_11/2–6s 6p¹⁰P_9/2 transitions.