Geometric route solving of the observed parasitic oscillation and analysis of parasitic oscillation suppression in an end-pumped zigzag slab laser

Abstract

The parasitic oscillations in an end-pumped zigzag slab laser are analyzed. The specific geometric route of the parasitic oscillation observed in experiment is deduced in detail for the first time. A numerical analysis of the gain and loss along the parasitic oscillations route is performed, and the critical condition of parasitic oscillations is calculated. The coating technology is employed to increase the losses along the parasitic oscillations route to suppress parasitic oscillations. The maximum output power of a short resonant cavity of the slab module and the maximum small signal gain of the slab amplifier increase by 21.4% and 17.4% after the suppression of parasitic oscillations, respectively.