机械剥离石墨烯被动谐波锁模掺铒光纤激光器

Passive Harmonic Mode-Locking in Er-Doped Fiber Laser Based on Mechanical Exfoliated Graphene Saturable Absorber

基于机械剥离方法,即通过胶带反复剥离高定向热解石墨,制备得到少层石墨烯,并将其作为可饱和吸收体实现了被动谐波锁模掺铒光纤激光器。在抽运功率约135 m W时,获得了中心波长1568.3 nm,脉冲宽度1.82 ps,3 d B带宽1.7 nm,重复频率1.646 MHz的基频锁模激光输出。通过增加抽运功率和调节腔内偏振,可以获得谐波锁模,谐波阶数最高达到基频的47阶(77.36 MHz)。同时,研究了不同阶谐波锁模时,输出功率、脉冲宽度和单脉冲能量的变化。

Passive harmonic mode-locking of erbium-doped fiber laser with graphene as a saturable absorber is proposed. Graphene saturable absorber is obtained via mechanical exfoliation method by peeling highly oriented pyrolytic graphite repeatedly. When the pump power is 135 m W, the laser operates at fundamental repetition rate of 1.646 MHz with pulse duration of 1.82 ps and 3 d B bandwidth of 1.7 nm. With the pump power and adjusting polarization in the cavity appropriately increasing, the laser operates at several harmonics of fundamental repetition rate and the highest repetition rate achieved is 77.36 MHz, which corresponds to the 47 th harmonic. The output power, pulse duration and single pulse energy for different harmonics have been studied.