0.017 nm, 143 ps passively mode-locked fiber laser based on nonlinear polarization rotation
Weixi Li, Zinan Huang, Xiangpeng Xiao, Zhijun Yan, Siyu Luo, Yingxiong Song, Chen Jiang, Yunqi Liu, Chengbo Mou
Abstract
Mode-locked lasers with ultra-narrow spectral widths and durations of hundreds of picoseconds can be versatile light sources for a variety of newly emergent applications. However, less attention seems to be given to mode-locked lasers that generate narrow spectral bandwidths. We demonstrate a passively mode-locked erbium-doped fiber laser (EDFL) system that relies on a standard fiber Bragg grating (FBG) and the nonlinear polarization rotation (NPR) effect. This laser achieves the longest reported pulse width (to the best of our knowledge) of 143 ps based on NPR and an ultra-narrow spectral bandwidth of 0.017 nm (2.13 GHz) under Fourier transform-limited conditions. The average output power is 2.8 mW, and the single-pulse energy is 0.19 nJ at a pump power of 360 mW.