Influence of stimulated Brillouin scattering on the temporal dynamics of an actively Q-switched double-clad fiber laser

The role of stimulated Brillouin scattering (SBS) during the active Q-switching of a typical high power double-clad fiber laser is experimentally and theoretically investigated. Our numerical model reproduces multiples Brillouin Stokes generation and the fast temporal dynamics which were experimentally observed. It clearly demonstrates that SBS is the cause of peak power enhancement effects such as giant pulse generation. The pulse formation process during the active Q-switching and the precise role of SBS in the pulse narrowing is detailed.