STIMULATED-BRILLOUIN-SCATTERING PROPERTIES OF SNCL4

Common liquid Brillouin media have poor optical and physical stability when they are pumped at high average powers. We demonstrate that tin tetrachloride, SnCl4, is stable and shows no thermal defocusing at 1064 nm for 20-ns pulses at fluences of 3 J/cm2 and a pulse-repetition frequency of 10 Hz. To characterize this new stimulated-Brillouin-scattering medium we measured the following stimulated Brillouin parameters: Brillouin shift at 35-degrees-C, nu-B = (2.21 +/- 0.02) GHz or omega-B = 7.37 x 10(-2) cm-1; temperature dependence of the Brillouin shift, d-nu-B/dT = -8.95 MHz/degrees-C; small-signal gain coefficient at line center, g0 = (11.2 +/- 0.5) cm/GW; Brillouin-gain linewidth, DELTA-nu-B = (182 +/- 12) MHz, which corresponds to a phonon relaxation time tau-B = 1.75 ns; and refractive index n = 1.36 at 1.064-mu-m and 25-degrees-C.