氧化石墨烯被动锁模掺镱光纤激光器多脉冲现象的实验研究

Experimental studies of multiple pulses in a passively ytterbium-doped fiber laser based on graphene-oxide saturable absorber

利用氧化石墨烯作为可饱和吸收体,在被动锁模全正常色散掺镱光纤激光器中研究了多脉冲的现象,在同一抽运功率不同偏振态下,实验获得了矩形脉冲谐波锁模、耗散孤子谐波锁模、准谐波锁模,脉冲峰值周期性调制,脉冲簇、脉冲束、混沌多重脉冲的多脉冲现象,插入激光腔内的2nm窄带滤波器具有限制增益带宽、对脉冲塑形、诱导多脉冲产生的作用,调节偏振控制器相当于改变腔内增益,是实现不同类型多脉冲现象的主要原因,本实验研究有利于加深对多脉冲动力学行为在正常色散区域氧化石墨烯锁模掺镱光纤激光器中的理解。

The different multiple pulse phenomena are experimentally studied in a passively mode-locked ytterbium-doped fiber laser based on graphene-oxide saturable absorber （GOSA） with net normal dispersion cavity. At the same pump power with different polarization orientations, we observe the multiple pulse phenomena, including harmonic mode-locking of rectangular pulses, dissipative solitons, quasi-harmonic mode-locking, periodical peak modulation, multipulse bunches, multipulse cluster, and chaotic multipulse. The inserted 2 nm narrow bandwidth filter is important for limiting the gain bandwidth and shaping pulses. Adjusting the polarization controller is equivalent to changing the gain in the laser cavity, which is the main reason for the formation of different multiple pulses states. This is the first time that different multiple pulses states have been observed in an-normal-dispersion Yb-doped fiber laser with graphene-oxide saturable absorber. These results could extend the understanding of multiple pulse dynamics in GOSA mode-locked fiber lasers.