A Nd:YAG laser oscillator Q-switched and mode locked via a nonlinear
mirror based on stimulated Brillouin scattering (SBS) and aided by an
acousto optical modulator (AOM) has been realised. A rate equation model
and a round trip model are used to describe the longitudinal mode
dynamics. Parameter variations of the nonlinear SBS mirror and the loss
modulating AOM in the resonator are investigated with regard to their
effect on the pulse duration and spectra of the pulses.