Spectral amplitude and phase control in a CPA laser system using adaptive optics in the stretcher

Summary form only given. As pulse duration is decreasing, it becomes mandatory to take into account the residual spectral phase that can´t be corrected in CPA laser systems. Up to date CPA systems are well corrected for chirp (/spl phi//sub 2/) and /spl phi//sub 3/. The remaining spectral phase defect reduces the amplified pulse contrast. Furthermore, gain narrowing in a Ti:sapphire amplifier limits the pulse duration to 30 fs. By controlling both spectral amplitude and phase we can reach pulses as short as 16 fs.