Transform-limited pulses from a mJ-class nonlinear fiber CPA-system by phase shaping

We experimentally demonstrate phase-shaping in fiber CPA-systems, providing pulse-energies at the mJ-level. The applied method is based on an analytical model describing the impact of SPM in CPA-systems. Using this phase-shaping technique nearly transform limited pulses are produced at B-integrals up to 10 rad. Compared to a nonlinear CPAsystem with the best performance being achieved by adjusting the compressor, operation of the same system using the phase-shaping method permits peak-power enhancement by a factor better than 2.