被动锁模掺Er^(3+)氟化物光纤激光器理论研究  

Theory study on passively mode-locked Er^(3+)-doped fluorine fiber laser

作　　者：王少奇[1,2,3,4] 邓颖[1,3] 李超[1] 王方[1] 张永亮[1] 康民强[1] 薛海涛[1] 罗韵[1] 粟敬钦[1,2,3] 胡东霞[1,3] 郑奎兴[1] 朱启华[1,2,3] 

机构地区：[1]中国工程物理研究院激光聚变研究中心,四川绵阳621900 [2]等离子体物理重点实验室,四川绵阳621900 [3]IFSA协同创新中心上海交通大学,上海200240 [4]中国工程物理研究院研究生院,北京100088

出　　处：《红外与激光工程》2016年第11期67-72,共6页Infrared and Laser Engineering

摘　　要：根据非线性薛定谔方程建立了基于可饱和吸收体被动锁模掺Er^(3+)氟化物光纤激光器的理论模型,研究了中红外超短脉冲在掺Er^(3+)氟化物光纤激光器中形成的物理机制,数值模拟了被动锁模掺Er^(3+)氟化物光纤激光器中中红外超短脉冲的演化过程,重点分析了掺Er^(3+)增益光纤长度,可饱和吸收体不饱和损耗对被动锁模掺Er^(3+)氟化物光纤激光器产生中红外超短脉冲的影响,并给出了参数设置范围。研究发现:当小信号增益系数、可饱和吸收体不饱和损耗、腔内净色散量为一定值,掺Er^(3+)氟化物光纤长度在一定范围时,才会出现稳定的锁模脉冲,且随着掺Er^(3+)氟化物光纤长度增加脉冲宽度变窄、光谱变宽、峰值功率增高;当掺Er^(3+)氟化物光纤长度、腔内净色散量、小信号增益系数为一定值时,可饱和吸收体不饱和损耗在一定的范围时可以得到稳定的锁模脉冲,且随着可饱和吸收体不饱和损耗的增加脉冲宽度变窄,光谱先变宽后变窄变化范围不大,峰值功率增加。Based on the Nonlinear Schr/Sdinger Equation（NLSE）, the theoretical model of psssively mode- locked Er3＋-doped fluorid fiber laser using a saturable absorber was set up, by which the mechanism of generating mid-infrared ultrashort pulse in the fiber laser was investigated. The numerical simulation focused on the evolution process of the mid-infrared ultrashort pulse in fluorine fiber laser. The impact of the Er3＋： fluorine gain fiber length and the saturable absorber unsaturated loss on the generation of mode-locked pulse was analyzed in detail, and the reasonable parameter range was determined. It is found that for a given set of small-signal gain, unsaturated loss, and net intracavity dispersion, the stable mode-locked pulses are achieved by tuning the Er3＋： fluorine gain fiber length within a certain range. With increasing the Er3＋： fluorine gain fiber length, the output pulse duration decreased gradually, while the increase of the spectrum width （FWHM） and the peak power are observed. Meanwhile, for a given set of Er3＋： fluorine gain fiber length, net intracavity dispersion and small-signal gain, the stable mode- locked pulses are also obtained by adjusting the saturable absorber unsaturated loss within a certain range. With the increase of the saturable absorber unsaturated loss, the output pulse duration decreases gradually, however spectral width broadens and then narrows, and peak power increases gradually.

关 键 词：光纤激光器 超短脉冲 中红外 氟化物光纤 

分 类 号：O439[机械工程—光学工程]