基于WS2可饱和吸收体的脉冲激光器研究

利用WS₂的可饱和吸收特性，在激光二极管侧面抽运Nd:YAG固体激光器Z型腔结构中分别实现了被动调Q和被动调Q锁模运转。实验表明:当泵浦电流为9.5 A时，开始启动调Q运转，当泵浦电流大于9.8 A时，调Q激光脉冲趋于稳定。当泵浦电流为12.8 A时，被动调Q输出的最大平均功率为466 mW，最窄脉冲宽度为3.205 μs，对应的重复频率为71.70 kHz，此时最大单脉冲能量为6.5 μJ。当泵浦电流达到13.4 A时，激光器实现调Q锁模运转。调Q锁模的最高输出功率为590 mW，调Q包络频率为71.98 kHz，单个调Q包络内的脉冲串重复频率123.1 MHz，每个调Q包络中包含369个脉冲，单脉冲能量为22.2 nJ。结果表明WS₂材料可以作为可饱和吸收体用于固体激光器中。

Pulse lasers based on WS2 saturable absorber

Based on the saturable absorption characteristics of WS₂, passively Q-switching and passively Q-switched mode locking operations of a side-pumped Nd:YAG solid-state laser were experimentally demonstrated in a self-designed Z-type four-mirror cavity structure. The Q-switching operation started under the pump current of 9.5 A and turned into a stable operation under more than 9.8 A. When the pump current was 12.8 A, the maximum average output power was 466 mW, the narrowest pulse width was 3.205 μs, the repetition frequency was 71.70 KHz, corresponding to the maximum pulse energy of 6.5 μJ.When the pump current was 13.4 A, a passively Q-switched mode locking operation was obtained. The maximum output power of passively Q-switched mode locking was 590 mW, the repetition rate of Q-switched pulse was 71.98 KHz, and the corresponding repetition rate of pulse train under single Q-switched pulse envelope was 123.1 MHz, and each Q-switched envelope contained 369 pulses with the single pulse energy of 22.2 n.The results show that the WS₂ material can act as the absorber for solid-state lasers.