Abstract

The application of stimulated Raman scattering to the development of semi-tunable lasers has received considerable attention over the last two years. Specific examples included the frequency conversion of excimer lasers in H₂ to the blue-green for naval communications applications, and the pulse compression of excimer lasers utilizing backward stimulated Raman scattering in CH₄ for laser fusion applications¹. These applications require a knowledge of the Raman scattering cross section (∂σ/∂Ω) as a function of wavelength for accurate modeling of the Raman gain process. Many Raman cross sections have been measured in the visible, but there are few measurements² below 350 nm. The cross section scales as the Stokes frequency to the fourth power times a resonance enhancement factor, usually assumed to be unity. We show here that the resonance enhancement factor for pump lasers in the uv can be a sizeable correction to the Raman scattering cross section and present absolute cross section data for the vibrational Q branch transitions for H₂ (4156 cm⁻¹), D₂ (2986 cm⁻¹), CH₄ (2917 cm⁻¹), N₂ (2331 cm⁻¹), and O₂ (1555 cm⁻¹) as a function of wavelength from 600-200 nm.

© 1983 Optical Society of America