Antiphase state in passivelyQ-switchedYb:YAGmicrochip multimode lasers with a saturable absorberGaAs

Abstract

We report on recent experimental results of the spontaneous antiphase dynamics that occurs in a laser-diodepumped multimode passively Q-switched microchip Yb: YAG (where YAG is yttrium aluminum garnet) lasers with a saturable absorber GaAs. We observe that the pulse sequence of the first mode characterized by one, two, and three pulses as a group and all the modes display an antiphase state as the pumping ratio rises. We modify the multimode rate equations to account for nonlinear absorption due to GaAs in the presence of spatial hole burning. We perform numerical simulations based on the proposed rate equations and reproduce the observed antiphase state of two and three active modes.