High-spectral-resolution stimulated Rayleigh-Brillouin scattering at 1 mu m

We have demonstrated stimulated Rayleigh-Brillouin scattering at a waveleng th of 1.064 mum, using an injection-seeded Nd:YAG laser as a pump laser and a tunable diode laser as a probe laser. Spectra with a good signal-to-nois e ratio are obtained despite the low probe-beam power and small gain coeffi cient in the infrared. Stimulated Rayleigh scattering is readily observable in organic and many other liquids because of absorption by the OH and CH o vertone or combination bands. The absorption also causes an asymmetry in th e stimulated Brillouin peak. A Rayleigh linewidth of 8 MHz is measured with this approach. (C) 2001 Optical Society of America.