Passively Q-switched and mode-locked laser performance of the mixed crystals with GaAs saturable absorber

By using the mixed crystals Nd:Lu0.33Y0.37Gd0.3VO4, Nd:Lu0.5Y0.5VO4 and Nd:Lu0.15Y0.85VO4 as laser media, the LD pumped passively Q-switched and mode-locked (QML) lasers with GaAs saturable absorber are realized. The average output power, the pulse width and the repetition rates have been measured and compared. The experimental results show that the passively Q-switched and mode-locked Nd:Lu0.33Y0.37Gd0.3VO4 laser can generate shorter pulse width with higher peak power due to broader fluorescence line-width. By considering the Gaussian distribution of the intracavity photon density and the influence of the continuous pump rate, the coupled rate equations for QML lasers with GaAs saturable absorber are given. The theoretical solutions of the equations are in agreement with the experimental results.