对基于808 nm端面抽运的半导体可饱和吸收镜(SESAM)锁模Nd∶YVO4激光器的输出特性进行研究,通过选择不同透过率的输出镜,设计一套针对不同输出功率需求的锁模激光器方案。首先系统地研究输出镜透过率对激光锁模功率和阈值的影响,当输出镜透过率为10%,抽运功率为8 W时,得到最高输出功率为2.58 W的连续锁模脉冲输出,转换效率为32.3%。当输出镜透过率为0.1%,抽运功率为1 W时,得到低阈值连续锁模脉冲输出,输出功率为0.58 mW。然后自主搭建自相关光路测量锁模脉冲,结合自相关曲线分析锁模激光器的寄生振荡情况,通过优化输出镜抑制寄生振荡,获得纯净的锁模脉冲,其脉冲宽度为13 ps,重复频率为150 MHz。

This study focuses on the output characteristics of an 808-nm laser diode (LD) end-pumped Nd∶YVO₄ mode-locked laser with a semiconductor saturable absorber mirror (SESAM). Further, a mode-locked laser with variable output power is designed by the selection of the output mirror transmittance. First, the influence of the output mirror transmittance on the laser mode-locked power and threshold is systematically studied. An output mirror transmittance of 10% and a pumping power of 8 W result in the highest output power of 2.58 W that corresponds to a conversion efficiency of 32.3%, whereas an output mirror transmittance of 0.1% results in a low continuous-wave mode-locked threshold of 1 W and an output power of 0.58 mW. Second, the mode-locked pulse width is measured by using a home-made autocorrelator; the parasitic oscillations of the laser are analyzed based on the autocorrelation traces. Thus, we obtain mode-locked pulses with a pulse width of 13 ps at a repetition rate of 150 MHz by optimizing the output mirror to suppress the parasitic oscillations.