掺铒光纤自发辐射宽带光源的带宽优化研究

Bandwidth optimization research of wide-band optical source with the Er3+-doped fiber amplified spontaneous emission

为了解决掺铒光纤放大自发辐射宽带光源的自然输出光谱中单峰造成的窄带宽问题,采用双程、后向光源结构消除抽运光输出,同时外接未抽运掺铒光纤以展宽可用带宽,进行了理论分析和实验验证;研究了掺铒光纤长度和光纤反射镜反射系数对光源输出光谱的影响,分析了外接未抽运掺铒光纤的长度对光源带宽的优化效果。结果表明,随着掺铒光纤长度的增加,放大自发辐射光谱C波段逐渐降低,L波段逐渐抬升;随着反射镜反射系数的增加,放大自发辐射光谱带宽提高;此外,当抽运掺铒光纤和外接未抽运掺铒光纤的长度分别为6 m和2 m时,放大自发辐射宽带光源输出带宽为50.31 nm,和未采用外接掺铒光纤时相比,带宽增加44 nm。上述研究结果可为宽带光源的性能优化提供参考。

In order to solve the natural narrow bandwidth of wide-bandwidth optical source with Er3+-doped fiber amplified spontaneous emission,the configuration of double-pass,backward pumped,and connected unpumped-fiber was proposed to eliminate the influence of pump source and broaden its bandwidth.The numerical simulation and experiment were carried out.The influence of Er3+-doped fiber length and reflection coefficient of fiber reflect mirror on the optical spectrum was analyzed in detail.The optimization effect of unpumped Er3+-doped fiber on the amplified spontaneous emission output spectrum was studied.The results show that,with increasing the length of pumped fiber,the C-band of the amplified spontaneous emission spectrum decreases slowly,and L-band raises.When the reflect coefficient of mirror increases,the bandwidth of amplified spontaneous emission was broadened correspondingly.The bandwidth of amplified spontaneous emission is 50.31 nm when the pumped and unpumped fiber is 6 m and 2 m respectively,which is improved 44 nm.All the results obtained could provide support for the design of wide-band optical source.