Spatiotemporal model of femtosecond pulse generation in Kerr-lens mode-locked solid-state lasers

A spatiotemporal model for the evolution process of the pulse and beam shapes in femtosecond Kerr-lens mode-locked solid-state lasers is presented. For different cavity configurations we comprehensively studied the dependence of the pulse and beam parameters on laser-control parameters such as pump rate, linear phase dispersion up to fourth order, self-phase modulation, and self-amplitude modulation owing to nonlinear resonator transmission. We determine the conditions for the ultimate shortest pulse duration. The influence of third- and fourth-order dispersion results in spectral sidebands, which are phase matched with the peak, of the principal spectrum. Excessive fourth-order dispersion yields a steady-state multipulse operating regime with constant peak separation. (C) 1998 Optical Society of America.