摘要
There are two different effects to generate group effect and Gires-Tournois effect. Both effects are delay dispersion by multilayer thin film mirrors： chirper employed to introduce desired dispersion in the designed mirror. Thus the designed mirror provides large dispersion throughout broad waveband. Such mirror can be used for dispersion compensation in Ti：sapphire femtosecond lasers. Most group delay dispersion of a 5-mm Ti：sapphire crystal can be compensated perfectly with only four bounces of the designed mirror.
There are two different effects to generate group effect and Gires-Tournois effect. Both effects are delay dispersion by multilayer thin film mirrors： chirper employed to introduce desired dispersion in the designed mirror. Thus the designed mirror provides large dispersion throughout broad waveband. Such mirror can be used for dispersion compensation in Ti：sapphire femtosecond lasers. Most group delay dispersion of a 5-mm Ti：sapphire crystal can be compensated perfectly with only four bounces of the designed mirror.
基金
This work was supported by the National Natural Science Foundation of China under Grant No. 60378005
