采用射频磁控反应溅射法和热退火处理制备了纳米Si/SiNx超晶格薄膜材料。把薄膜作为可饱和吸收体插入激光二极管泵浦的平凹腔Nd∶YVO4激光器内,实现了1 342 nm激光的被动调Q运转,获得脉冲宽度约20 ns、重复频率33.3 kHz的调Q脉冲序列输出。分析了纳米Si/SiNx薄膜可饱和吸收的产生机制,认为双光子吸收是产生1 342 nm激光被动调Q的主要原因。对纳米Si/SiNx薄膜材料调Q激光器的速率方程组进行了数值求解,得到的调Q脉冲时间宽度的理论值和实验结果基本相符。 The nano-Si / SiNx superlattice thin films were prepared by RF magnetron reactive sputtering and thermal annealing. The thin film was inserted into a laser diode pumped Nd: YVO4 laser as a saturable absorber to achieve a passive Q-switched operation of 1 342 nm laser, and a Q-switched pulse sequence with a pulse width of about 20 ns and a repetition frequency of 33.3 kHz Output. The mechanism of saturable absorption of nano-Si / SiNx films is analyzed. It is considered that two-photon absorption is the main reason for the passive Q-switching at 1 342 nm. The rate equations of the Q-switched Q-switched laser of nanocrystalline Si / SiNx thin films were numerically solved, and the theoretical values ​​of the Q-switched pulse duration were basically consistent with the experimental results.