环形铥光纤激光器中台阶形脉冲的产生  

Generation of step shaped pulses in a thulium doped ring fiber laser

作　　者：吴佟 朱光辉 孙儒峰 龙润泽 张昆 张利明 赵鸿 WU Tong;ZHU Guang-hui;SUN Ru-feng;LONG Run-ze;ZHANG Kun;ZHANG Li-ming;ZHAO Hong(Key Laboratory of Solid State Laser Technology,Beijing 100015,China)

机构地区：[1]固体激光技术重点实验室,北京100015

出　　处：《激光与红外》2024年第8期1188-1192,共5页Laser & Infrared

摘　　要：研究了基于非线性偏振旋转(NPR)锁模的铥光纤激光器中台阶形脉冲的产生。通过在NPR锁模器件前后各引入一段长度分别为100 m和350 m长的SMF-28光纤以增强腔内非线性和积累负色散,得到底座宽度为50 ns,重复频率为615.6 kHz,信噪比为55 dB的双波长(波长分别为2025 nm和2034 nm)台阶形脉冲。发现仔细调节偏振控制器和改变泵浦功率可以精细调节台阶形脉冲的形态。通过研究发现台阶形脉冲是由两个矩形脉冲组合而成,且前后泵浦对两个矩形脉冲的影响不同,通过改变偏振态能实现能量在前后两个矩形脉冲之间的转化。本实验为研究被动锁模光纤激光器脉冲动力学和脉冲整形提供了良好的实验平台。In this paper,the generation of stage shaped pulses in thulium fiber lasers based on nonlinear polarization rotation mode locking is investigated.By introducing a segment of SMF-28 fiber with a length of 100 m and 350 m respectively before and after the nonlinear polarization rotation mode locking device to enhance intracavity nonlinearity and accumulate negative dispersion,a dual-wavelength(wavelengths of 2025 nm and 2034 nm,respectively)step-shaped pulse with a base width of 50 ns,a repetition frequency of 615.6 kHz,and a signal-to-noise ratio of 55 dB is obtained,and it is found that carefully adjusting the polarization controller and changing the pump power can finely adjust the shape of step shaped pulses.Through the study,it is found that the stepped pulse is formed by the combination of two rectangular pulses,and the front and rear pumps have different influences on the two rectangular pulses,and the energy can be realized by changing the polarization state between the front and rear two rectangular pulses.The experiment provides a good experimental platform for studying the pulse dynamics and pulse shaping of passive mode-locked fiber lasers.

关 键 词：非线性偏振旋转 铥光纤激光器 锁模 台阶形脉冲 双波长 

分 类 号：O437[机械工程—光学工程] TN248[理学—光学]