Cancellation of B-integral accumulation for CPA lasers

The B-integral accumulated in a chirped-pulse-amplification (CPA) laser can be canceled using a semiconductor with a negative nonlinear index of refraction. We demonstrate this experimentally using GaAs at 1.053 /spl mu/m. The compressed-pulse duration was broadened due to self-phase modulation (SPM) of the chirped pulse. It was reduced to its unmodulated value with substantial wing reduction after passing through a semiconductor wafer before compression. Optimum semiconductor sample parameters for minimizing the B-integral such as gap energy, nonlinear and linear absorption, nonlinear refraction, and thickness for different pulse durations and intensities are discussed.