被动锁模光纤激光器的耦合输出比  

Output Coupling Ratio in Passively Mode-Locked Fiber Laser

作　　者：赵羽[1] 赵德双[2] 刘永智[1] 黄琳[1] 

机构地区：[1]电子科技大学光电信息学院,四川成都610054 [2]电子科技大学物理电子学院,四川成都610054

出　　处：《中国激光》2009年第4期794-798,共5页Chinese Journal of Lasers

基　　金：国家自然科学基金(60736038);国家863计划(2007AA01Z269);国防预研基金(9140A02040106DZ0222)资助课题

摘　　要：基于环形腔被动锁模光纤激光器的基本原理,对影响其输出特性的关键因素——耦合输出比(R)作了理论和实验研究。理论仿真结果表明.要得到高质量的脉冲,激光器腔内增益与耦合输出比存在一最佳比值,小信号增益为7.5 dB时,耦合输出比应在30%左右。实验中取3 m长的增益光纤,分别采用5%,10%～40%和60%～90%的耦合输出比搭建环形腔被动锁模光纤激光器。实验结果对比分析表明,耦合输出比对激光器的输出特性有重要影响.R取5%～10%间时脉冲谱宽最宽(可达25.4 nm)且谱宽调谐范围较大(>12 nm),R=10%和30%时脉冲波动幅度最小,R=70%左右时单脉冲能量最大(达3.86 nJ)。另外,取R=30%.可在脉冲幅值波动较小的基础上获得最大的脉冲能量;而R=10%时为保证脉冲波动小、谱宽宽和能量大的平衡点。取3 m长的增益光纤和R=10%的激光器,获得了重复频率15.87 MHz,谱宽25.4 nm,单脉冲能量约0.52 nJ的脉冲激光,这些特性不会受到工作台振动、激光器搬动及普通温度变化等因素的影响,脉冲幅值存在约4%的波动。The impact of output coupling ratio in passively mode-locked fiber ring laser was studied based on basic principle of passively mode-locked fiber ring laser. Theoretical simulation shows that there is a best ratio between gain and output ratio. And the ratio should be 30% when the small single gain is 7.5 dB. Ratio（ R ） of 5%, 10% to 40 %, and 60 % to 90 % was experimentally carried out when the length of gain fiber was 3 m. The experiments show that, whenR =5% to 10%, spectrum width is the widest （about 25.4 nm） and tunable range of spectrum width is wider （〉12 nm）. The fluctuation of pulse magnitude is the smallest when R = 10% and 30%. The single pulse energy is the largest one （about 3.86 nJ） when R =70 %. To get the highest pulse energy while keep the pulse stable theR should be 30%. To make the pulse spectrum wider, the pulse energy higher while keep the output stable, theR should be 10%. The fiber laser with R = 10% and Er^3- -doped fiber（EDF ）length of 3 m was experimentally carried out, with the repitition rates of 15.87 MHz, spectrum width of 25.4nm and single pulse energy of 0.52nJ, which wouldn＇t be impacted by librations of desk, movement of fiber laser or temperature variation. The fluctuation of pulse magnitude is 4 %.

关 键 词：激光器 光纤激光器 被动锁模 稳定性 耦合输出比 

分 类 号：TN248.1[电子电信—物理电子学]