【摘要】 根据飞秒脉冲锁模钛宝石激光器脉冲压缩的要求,介绍了负色散镜补偿色散的基本原理及其特点。详细阐述了优化Gires Tournois(OG T)镜的设计过程,并通过计算机优化得到理想设计膜系。采用离子束溅射的方法镀制了优化Gires Tournois镜。测量了优化Gires Tournois镜(编号为OGT#1)的透射率和群延迟色散,并与设计值进行了比较,分析了实测值产生偏差的原因,从而对镀膜参量进行了相应的调整,制造了第二批优化 Gires Tournois镜(编号为OGT#2)。将优化 Gires Tournois 镜用于钛宝石激光器振荡级内,单程 5 次通过三个优化Gires Tournois镜,补偿了激光器腔内色散,实现了飞秒锁模脉冲运转。用OGT#1先进行了实验,获得32 fs的脉冲和46 nm的光谱宽度。用调整参量后的 OGT#2 进行了实验,获得了 15 fs的超短脉冲和 91 nm的光谱宽度。实验很好的验证了负色散镜补偿色散的优点,为国内啁啾镜的研制创造了条件。更多还原

【Abstract】 According to the mode locked femt second Ti∶sapphire laser pulse compression, the characteristics and principles of dispersion compensation of negative dispersion mirrors were introduced. Optimized Gires Touronis (OG T) mirrors were designed and fabricated. OG T mirrors were deposited by means of ion beam sputtering onto superpolished substrates. The transmittance and group dispersion delay of first fabricated OG T (OGT#1) mirrors were measured. Film coating parameters were adjusted according with design value. After that, second fabricated OG T (OGT#2) mirrors were fabricated. Dispersion was compensated by 5 bounces during 3 OG T mirrors from mode locked femtosecond Ti∶sapphire laser. 32 fs pulse (46 nm spectrum width) and 15 fs pulse (91 nm spectrum width) were obtained respectively by OGT#1 and OGT#2. The excellent features of negative dispersion mirrors were proved by the experiment and the fine chirped mirrors could be fabricated.更多还原