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Spectral Characteristics of Ultrashort Pulses in Kerr-lens Mode-Locked Lasers

V. L. Kalashnikov·E. Sorokin·I. T. Sorokina
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Abstract

A number of factors that influence spectral position of the femtosecond pulse in a Kerr-lens modelocked Cr:LiSGaF laser have been identified: high-order dispersion, gain saturation, reabsorption from the ground state, and stimulated Raman scattering. Using the one-dimensional numerical model for the simulation of the laser cavity, the relative contributions of different factors have been compared. The Raman effect provides the largest self-frequency shift from the gain peak (up to 60 nm), followed by the gain saturation (25 nm), while the high-order dispersion contribution is insignificant (5 nm). Comparison with the experimental data confirm that the stimulated Raman scattering is a main cause of the ultrashort pulse self-frequency shift observed in Cr:LiSGaF and Cr:LiSAF lasers

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V. L. Kalashnikov, E. Sorokin, I. T. Sorokina. 2001-07-07. Spectral Characteristics of Ultrashort Pulses in Kerr-lens Mode-Locked Lasers. https://arxiv.org/abs/physics/0101004

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