Chirped-pulse amplification with a fiber stretcher and a grism compressor

In chirped-pulse amplification (CPA) lasers, pulses are temporally stretched by a factor of ~103, and to achieve good pulse compression it is necessary that the dispersion of the compressor match that of the stretcher. The original CPA lasers used a single-mode fiber to stretch and a grating pair to compress; however, the mismatch in third-order dispersion between the fiber and the grating made sub-picosecond compression impossible. The fiber stretcher was abandoned in favor of the more complicated grating-pair stretcher, which more closely matched the dispersion of the grating compressor.