介绍了一种新型半导体可饱和吸收镜(SESAM)的原理与特性,并用它来实现掺铒光纤激光器的锁模飞秒脉冲的生成。这种新型宽带SESAM调制深度可以达到20%,用在1.5μm波段的环形腔掺铒光纤激光器里,实现自启动锁模。锁模光谱以1559 nm为中心,半峰全宽为9 nm,锁模激光脉冲串重复频率为25.6 MHz,输出功率14 mW,自相关仪测得脉宽为170 fs。 The principle and characteristics of a new type of semiconductor saturable absorption mirror (SESAM) are introduced and used to generate the mode-locked femtosecond pulses of erbium-doped fiber lasers. The new broadband SESAM modulation depth of up to 20%, used in the 1.5μm band cavity erbium-doped fiber laser, to achieve self-starting mode-locking. The mode-locked spectrum is centered at 1559 nm and the full width at half maximum is 9 nm. The mode-locked laser pulse repetition frequency is 25.6 MHz and the output power is 14 mW. The pulse width measured by the autocorrelator is 170 fs.