Influence of pulse shape in self-phase-modulation-limited chirped pulse fiber amplifier systems

Our investigation is focused on the influence of the temporal pulse shape in chirped pulse fiber amplifier systems in which the recompression is limited due to a nonlinear chirp caused by self-phase modulation (SPM). We show that specific pulse shapes can overcome the usual limit but have to be maintained during amplification, which is not fulfilled if gain shaping occurs. We analyze numerically the possibility of spectral preshaping in order to prevent gain shaping and nonlinear distortion due to SPM.