基于倾斜光纤光栅的连续可调谐锁模激光器

Continuously Tunable Mode-Locked Fiber Laser Based on Tilted Fiber Grating

以45°倾斜光纤光栅为起偏器,采用非线性偏振旋转技术,搭建了一台基于45°倾斜光纤光栅和锥型光纤的波长可调谐被动锁模光纤激光器。当输入抽运功率为454 mW时,可实现稳定的锁模脉冲输出,输出脉冲的中心波长为1568.8 nm,输出功率为2.31 mW,3 dB带宽为4.5 nm,脉宽为1.3 ps。锥型光纤作为可调节衰减器,改变了腔内的损耗,实现了波长从1568.8 nm到1560.24 nm的连续可调谐。该激光器可以应用在传感、光谱测量和通信等领域。

In this study, we demonstrate a wavelength-tunable passively mode-locked fiber laser based on a 45° tilted fiber grating and a tapered fiber using the nonlinear polarization rotation technique. Further, stable mode-locked pulses with a central wavelength of 1568.8 nm and output power of 2.31 mW can be obtained when the input pump power is increased to 454 mW. Accordingly, the 3-dB spectral bandwidth and pulse width are 4.5 nm and 1.3 ps, respectively. Subsequently, the central wavelength of the pulse can be continuously tuned from 1568.8 nm to 1560.24 nm using the tapered fiber as an adjustable attenuator to modulate the cavity loss. The demonstrated fiber laser can be used in several fields, including sensing, spectroscopy, and telecommunications.