We describe the results of an extensive study of transient stimulated Raman scattering in hydrogen gas. Measurements of self-oscillation thresholds, conversion efficiency, and the dependence of small-signal amplification on the pump energy and gas pressure are presented. Strong dependence of the amplification on the self-phase modulation of the pump and seed-Stokes pulses, on their relative time of arrival at the Raman amplifier, and on the seed-Stokes pulse asymmetry has been observed. The experimental measurements are compared with theoretical predictions that are based on extensions of published transient theories to take into account the spatial and temporal profiles of the pulses as well as their phase modulation. Excellent agreement with the theory, especially with regard to the scaling of the small-signal amplification with pump-pulse energy, is obtained when all the specific characteristics of the pump and Stokes pulses are included in the calculations.
© 1988 Optical Society of America
M. D. Duncan, R. Mahon, L. L. Tankersley, and J. Reintjes, "Transient stimulated Raman amplification in hydrogen," J. Opt. Soc. Am. B 5, 37-52 (1988)