Single-shot wave-front measurements of high-intensity ultrashort laser pulses with a three-wave interferometer.

A simple new three-wave interferometric technique is used to measure, for what is believed to be the first time, the wave front of femtosecond ultrahigh-peak-power pulses carrying a strong B integral (B = 5.26+/-0.15) in a single shot. Wave-front distortions of a terawatt-class laser system are measured with good accuracy (lambda/50) and discussed. These distortions can significantly reduce the focused peak intensity, emphasizing the necessity of implementing adaptive optics in ultrahigh-intensity chirped-pulse amplification lasers.