双波长可切换飞秒锁模光纤激光器

报道了基于非线性偏振旋转技术的双波长可切换飞秒锁模光纤激光器。通过改变泵浦功率以及偏振控制器状态,激光器在波长1533.2 nm和1557.2 nm处可实现双波长锁模,两个波长的间隔为24 nm。在这两个波长之间还可实现可切换运作,对应的3 dB带宽分别为5.53 nm和4.69 nm,脉冲宽度分别为730 fs和890 fs,双波长可切换锁模的成因是NPR诱导的梳状滤波效应。此外,由于孤子能量量化效应,实验中还观察多脉冲锁模。实验结果有助于人们深入了解双波长可切换锁模光纤激光器的动力学特性。

Switchable dual-wavelength femtosecond mode-locked fiber laser

Switchable dual-wavelength femtosecond mode-locked fiber laser based on nonlinear polarization rotation(NPR)is reported in this paper.By changing pump power and the state of the polarization controllers,the dual-wavelength mode locking is realized in the fiber laser,which has a wavelength separation of 24 nm with two central wavelengths of 1533.2 nm and 1557.2 nm.Switching operation can also be realized between the two wavelengths.The corresponding 3 dB spectral widths are 5.53 nm and 4.69 nm,respectively.The corresponding pulse durations are 730 ps and 890 ps,respectively.The switchable dual-wavelength mode locking could be attributed to comb filter effect induced by NPR.In addition,due to energy quantization effect,multi-pulse mode locking is also observed in the fiber laser.The results would give further insight towards understanding the dynamic characteristics of switchable dual-wavelength mode-locked fiber laser.