Peak-power scaling induced by spectral clipping in nonlinear CPA-systems

In this work we present a new method for peak-power scaling in nonlinear CPA-systems. In conventional CPA systems temporal stretching is used to avoid high peak powers developing during the amplification process. However, if the peak power of the stretched pulse is high enough, a considerable amount of nonlinear spectral phase shift (as described by the B-integral) can be accumulated due to self-phase modulation. Consequently, reduced peak powers and pulse shape degradation will be obtained after compression. Such systems are referred to as nonlinear CPA-systems. In addition to the simulations, we experimentally verified the theoretical predictions by applying our new technique to a fiber CPA-system. These experiments show a significant increase of peak-power and an improvement of pulse quality when the spectrum is clipped.