In this paper, the pulse waveform of stimulated Brillouin scattering (SBS) is investigated experimentally and theoretically. The variations of SBS pulse waveform with pump parameters, structural parameters and medium parameters are experimentally investigated with a Nd∶YAG Q-switched laser，and numerically simulated using SBS theory model. The theoretical calculations are in good agreement with the experimental results. The results indicate that modulation of pulse waveform is difficult to realige with low pump energy, short focal length, long lens-cell distance and long phonon life time. The influence of the pump parameters, structural parameters and medium parameters on SBS pulse waveform is discussed extensively.

In order to measure the Brillouin linewidth of SBS medium, a method using mixture media in two-cell stimulated Brillouin scattering (SBS) system is proposed, which uses the medium to be measured as amplifier medium and the mixture media as generator medium. The profile of gain coefficient versus the difference of Brillouin frequency shift is fitted with Lorentzian curve. The width at half-maximum of this curve is the Brillouin linewidth. In the experiment, using Nd:YAG Q-switched laser system and CCl4/C6H6 mixture, we measured the Brillouin linewidth of SBS media tetrachloroethylene (C2Cl4), hexachlorobutadiene (C4Cl6), acetone (C3H6O) and n-hexane (C6H14). The results show that the measured values are close to those calculated or published by other authors.