Fig. 1. The optical setup. L1–L5 denote anti-reflection coated plano-convex lenses. CMs1 and CMs2 are two pairs of chirped mirrors. SP-filter denotes a dielectric short-pass filter with a cut-off wavelength of 1025 nm. The yttrium aluminum garnet plate is not used in any of the experiments except for the process of contrast measurement using a second-order correlator.

Fig. 2. (a) Spectra of the input (black solid curve), after four 0.5-mm-thick sapphire plates (red dashed curve), after two 2-mm-thick sapphire plates (yellow dotted curve), after the SP-filter (purple solid curve) and after the seed pulse (green dotted curve). (b) Retrieved temporal profile after CMs1 and the corresponding FTL pulse.

Fig. 3. (a) Seed pulse spectra at five different positions. Inset: illustration of the five positions being sampled. (b), (c) TG-SRSI spectra and the retrieved spectral phase. (d) FTL and retrieved TG-SRSI temporal profiles, respectively.

Fig. 4. (a)–(c) Spectral stabilities characterized at positions of A–C. (d)–(f) The corresponding power stabilities by integrating spectral intensity (red curve) and measured by a power meter (black curve).

Fig. 5. (a)–(d) Near-field beam profiles of the input, after passing one plate in stage 1 and four plates in stage 1, and the output. (e) SAC intensities of the input and output pulses.