Theoretical and experimental investigation of injection seeded Nd:YAG zigzag slab ring lasers

•Spectral purity increases with the increase of injection intensity.•Spectral purity increases with the decrease of detuning frequency.•Frequency locking range increases for both high injection intensity and high gain. A comprehensive theoretical and experimental investigation of injection seeded Nd:YAG zigzag slab ring lasers is presented. The effects of injected intensity and detuning frequency on the dynamic process of mode competition are analyzed. A stable single frequency injection seeded Nd:YAG zigzag slab ring oscillator has been built by using the ramp-fire technique with a RbTiOPO4 phase modulator. A linear ramp voltage is used and the detuning frequency is precisely controlled by firing the Q-switch with an adjustable delay time after the resonance condition. Both the simulation and the experiments carried out at various injection conditions have demonstrated that the spectral purity of the output pulse increases with the increase of injected intensity and with the decrease of detuning frequency, and that the frequency locking range increases for both high injected intensity and high gain. The experimental measurements of output pulse energy and pulse width are also in good agreement with the theoretical results.