基于传播圆补偿像散的被动锁模激光器谐振腔设计方法  

Method of designing astigmatic compensation cavity for mode-locked laser based on propagation circle

作　　者：张小军[1] 杨富[2] 王勇刚[3] 孙利群[4] 文侨[1] 牛憨笨[1] 

机构地区：[1]深圳大学光电工程学院,光电子器件与系统(教育部,广东省)重点实验室,深圳518060 [2]河北北方学院理学院,张家口075000 [3]香港理工大学应用物理系 [4]清华大学精密仪器与机械学系,北京100084

出　　处：《物理学报》2013年第2期298-304,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61108026;61001184;61101175);高等学校博士学科点专项科研基金(批准号:20114408120001);广东高校优秀青年创新人才培养计划项目(批准号:LYM11107);深圳市科技研发资金重点实验室提升发展项目(批准号:CXB201005240011A);深圳大学科研基金资助面上项目(批准号:201033)资助的课题~~

摘　　要：由于超短脉冲激光器的谐振腔大都采用多镜折叠的形式,像散已成为影响锁模激光器性能优劣的重要问题.本文提出了一种基于传播圆补偿像散的被动锁模激光器谐振腔设计方法,该方法简单、直观、高效,容易找到补偿像散的最佳位置.理论研究表明,当SESAM位于子午和弧矢传播圆交汇处附近时,SESAM处的子午光斑和弧矢光斑大小几乎相等,像散得到补偿.该谐振腔对外界干扰引起的腔镜振动和热透镜焦距的变化均不敏感,谐振腔的抗干扰性很强.实验研究表明,当SESAM位于子午和弧矢传播圆交汇处附近时,锁模激光器可获得稳定连续的锁模激光脉冲,且激光器的抗干扰性很强.本文的理论研究与实验结果相一致.The cavities of ultrashort pulsed lasers are mostly based on folded resonators with multi-mirrors. Astigmatism is an important issue to affect the performance of the mode-locked laser. An effective method of astigmatic ally compensating a continuous-wave passively mode-locked laser is presented in this paper. This method, in which the resonator propagation circle graphic theory is used, is easy and intuitive to seek the optimal location of the semiconductor＇saturable absorber mirror （SESAM）, where the astigmatism can be compensated. Theoretical results show that the tangential and the sagittal spot size at the SESAM are equal and that the astigmatism can be compensated, when an SESAM is located at the tangential and the sagittal propagation circle intersection. The mode-locked resonator is insensitive to external perturbation including the vibration and the change of the thermal lens focal length, which leads to the instability of the mode locking operation. The antijamming ability of the resonator is outstanding. The experimental results indicate that the mode-locked laser works in a stabilized continuous-wave mode locking state and operates extremely steadily, when the SESAM is located at the tangential and the sagittal propagation circle intersection. The experimental results of the mode locking lasers show good agreement with the theoretical studies.

关 键 词：连续锁模 像散补偿 半导体可饱和吸收镜 传播圆 

分 类 号：TN248[电子电信—物理电子学]