钛宝石激光器中用优化Gires-Tournois镜产生15fs脉冲

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—Tourn

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.