基于布拉格光栅的多波长掺饵光纤激光器实验研究

Experimental study on multi wavelength erbium-doped fiber laser based on FBG

掺铒光纤具有较高的增益和抽运效率,在室温下是均匀展宽类型的增益介质,导致同一腔内得到的多波长激光会存在模式竞争以及模式跳变,较难实现多波长激光的同时振荡。本文利用光纤布拉格光栅的窄带滤波特性,以相位掩模法和点对点法制成的FBG及两者串接作为选频器件,设计并搭建多波长光纤激光器系统,实验实现了光纤激光器的多波长输出。通过对激光输出功率与输出谱线的实验研究与分析,发现在模式竞争过程中,能量高的激光模式最后总会成为胜者,调整激励电流、光栅接入方式可控制多波长掺饵光纤激光器波长输出特性。

Erbium doped fiber has high gain and pumping efficiency and is a uniform broadening type of gain medium at room temperature.But it can cause the mode competition and mode hopping,which leads to simultaneous oscillation of multi wavelength lasing very difficult in the laser cavity.Using the narrowband filter characteristics of FBG,a multi wavelength optical fiber laser system is designed and built through the phase mask method of FBG,point to point FBG and two series of fused FBG as frequency selection devices.This designed system therefore can realize the multi wavelength transmission of fiber laser.Through the experimental study and analysis of the output power and the output spectrum of the laser,it is found that in the model competition,the laser mode with high energy will eventually become the winner.The output characteristic of multi wavelength erbium doped fiber laser can also be controlled by adjusting the exciting current and grating access mode.