Stimulated Brillouin scattering from N2 and CH4 using a giant-pulse laser has been observed in an arrangement whereby the laser cannot relase and amplify the back-scattered radiation. This allows a quantitative study of the parameters affecting stimulated Brillouin scattering. The back-scattered beam converges at the same angle at which the laser beam diverges. The Brillouin component can have a narrow spectral width, one-third that of the laser itself, and in some cases can have a duration of only a few nanoseconds. N2 at high pressure can back-scatter as much as 45% of the incident power. The speeds of sound in CH4 and N2 have been measured at lower pressures than were previously reported.
© 1966 Optical Society of America
Original Manuscript: January 20, 1966
Published: June 1, 1966
T. A. Wiggins, R. V. Wick, and D. H. Rank, "Stimulated Effects in N2 and CH4 Gases," Appl. Opt. 5, 1069-1072 (1966)