Wavefront correction and aberrations pre-compensation in the middle of Petawatt-class CPA laser chains

Recent works demonstrated that is possible, by using a deformable mirror to correct aberrations at the end of the amplification chain, to obtain an improvement of the Strehl Ratio up to 90%. The problem of damage of optical components by spatial modulations and hot spot, especially in chirped pulse amplification laser chain, is usually underestimated, due to the difficulty of correlating the damages induced on the optical surfaces to the beam modulations. A new approach of the problem of damage in CPA laser chain, based on the analysis of temporal and above all spatial modulations of the stretched beam, enhances the importance of the evolution of the phase residues of the deformable mirror, responsible of hot spots formation.