Complex spatiotemporal coupling distortion pre-compensation with double-compressors for an ultra-intense femtosecond...

In an ultra-intense femtosecond chirped-pulse amplification laser, the imperfect diffraction wave-fronts of the second and the third gratings of the compressor, where spatio-spectral coupling exists, could introduce a complex spatiotemporal coupling distortion (STCD) and degrade the pulsed beam in both near- and far-fields. Here, we propose a method of double-compressors for pre-compensation. By inserting a scaled down compressor (small compressor) with a deformable retro-reflection mirror into the beam-line, the frequency-dependent wave-front distortion, i.e., the complex STCD, could be removed. We simulate the results in two different ultra-intense femtosecond lasers with 80 and 400 nm bandwidths for comparison, and near ideal focused peak intensities could be obtained in both cases. Meanwhile, the influences of several miss-matching effects, which might appear in engineering, are also analyzed and discussed for applications.