环形铥光纤激光器中脉冲簇及其簇群的产生

本文研究了基于非线性偏振旋转锁模的铥光纤激 光器中脉冲簇及脉冲簇群的产生。通 过在环形腔内引入两段长度分别为100 m和350 m的SMF-28光纤来增强腔内非线性和色散,从 而产生了脉宽为30 ns的束缚态脉冲簇。一 个束缚态脉冲簇可以产生12个振幅不同但时间 间隔相同的子脉冲。发现调节偏振控制器角度可以改变脉冲簇宽度以及子脉冲个数,进一步 调节还可使子脉冲分离而形成脉冲簇群。脉冲簇群形成有规律间隔的准量子化分布,其分离 的子脉冲脉宽为2.8 ns。实验中还产生了稳定的二次谐波锁模脉冲簇 ,并发现子脉冲的多种形态组合形式。

Generation of pulse bundles and bundle groups in a mode-locked Tm-doped fiber ring laser

The generation of pulse bundles and bundle groups are investigated in a mode-locked Thulium-doped fiber laser modulated by nonlinear polarization ro ta tion.Stable bound pulse bundles with a duration from 30to 50ns are generated from the cavity in which nonlinearity and dispersion are enhanced by inserting t wo pieces of SMF-28with lengths of 100m and 350m,respectively,into a ring c avity.One bound pulse bundle can produce up to 12sub-pulses with varying ampl i tudes but the same time interval.It is found that by rotating the polarization controllers,the pulse duration and the number of sub-pulses of a bound bundle c an be adjusted,furthermore,some of them can be expelled from the bundle to for m a bundle group.Inside the bundle group,its distribution is regularly organiz ed with quasi-quantized separations,where the pulse duration is 2.8ns.Stable second harmonic mode-locking pulse bundles are generated as well.In this case, the pulse bundle is found to present a combination of multiple pulse forms.