Detailed studies and control of intensity-related dynamics of femtosecond frequency combs from modelocked Ti : Sapphire lasers

Abstract—The authors have conducted detailed experimental investigations of the intensity-related dynamics of the pulse repetition and carrier-envelope offset frequencies of passively mode-locked Ti:sapphire lasers. Two different laser systems utilizing different intracavity dispersion compensation schemes are used in this study. Theoretical interpretations agree well with experimental data, indicating that intensity-related spectral shifts, coupled with the cavity group-delay dispersion, are important in understanding the dynamics of the frequency comb. Minimization of spectral shifts or the magnitude of group-delay dispersion leads to minimization of the intensity dependence of the femtosecond comb. Index Terms—Lasers, nonlinear optics, solid state lasers, ultra-fast optics. I