Correction of the residual spectral phase in a CPA laser system using a deformable mirror in the stretcher

Summary form only given. As the pulse duration is decreasing, it becomes mandatory to take into account the residual spectral phase that can´t be corrected in CPA systems. Up to date CPA systems are well corrected for /spl phi//sub 2/, (chirp) and /spl phi//sub 3/. The remaining spectral phase defect reduces the contrast of the amplified pulse. We propose the use of a deformable mirror (DM) in a CPA setup to control the spectral phase. The DM is included in the stretcher instead of being part of an added zero dispersion line usually used for pulse shaping. The spectral phase is measured using a Spectral Phase Interferometry for Direct Electric Field Reconstruction setup (SPIDER). This spectral phase is used to control the DM shape in a closed loop configuration.