非线性光纤环形镜掺铒光纤激光器的实验研究

为了研究掺铒光纤激光器超短脉冲的产生,采用增益平坦型掺铒光纤放大器、两个偏振控制器以及3个耦合器,利用非线性光纤环形镜加成脉冲锁模技术,通过改变偏振控制器的方向,获得最大输出功率为0.6mW的脉冲输出,对应的光谱宽度9nm、中心波长1561nm、脉冲宽度434ps、脉冲的重复频率为1.1MHz.该脉冲经过掺铒光纤放大器放大后,最大输出功率为10.8mW.放大后锁模脉冲的中心波长保持不变、光谱带宽稍有变窄、输出功率明显增大、脉冲宽度展宽为495ps.实验结果表明,采用商用的掺铒光纤放大器可实现结构简单、调节方便的掺铒光纤激光器超短脉冲输出,且掺铒光纤激光器可以实现自启动,并长时间稳定锁模工作.

Experimental study Er3+-doped fiber laser based on the nonlinear optical loop mirror

To study the generation of ultrashort pulse in Er3 -doped fiber laser,the fiber laser was composed of a gain-flattened erbium doped fiber amplifier(EDFA),two polarization controllers(PCs) and three couplers.A nonlinear optical loop mirror was used for mode-locking.By adjusting the position of PCs,the pulse at 1561nm at a repetition rate 1.1MHz was obtained.The maximum output power of the pulse was 0.6mW with 434ps pulse width and 9nm spectrum width.After amplified by EDFA,the maximum power of the output pulse is 10.8mW and the center wavelength did not change,the spectrum width became slightly narrow,the output power increases greatly and the pulse width of the amplified pulse was 495ps.The experimental results show that:the ultrashort pulse could be generated by the Er3 -doped fiber laser using a commercial EDFA.The self-starting of the mode-locked fiber laser can be achieved easily and the mode-locked operation can be hardly influenced by the experimental environment.