Fig. 1. Optical schemes of the (a) AFGC and (b) SSGP compressor. G1–G4 are diffraction gratings; L = L₁+ L₂. In the four beam profiles, the dark gray areas contain full spectra, and the red and blue areas contain partial longer and shorter spectra, respectively.

Fig. 2. (a) Spectral profile. (b) Input beam with five Gaussian shape hot spots and different FWHM diameters (10, 20, 40, 80 and 160 mm, respectively). (c) Output beam from the SSGP compressor with the introduced 520 mm spatial chirp. (d) Intensity profiles at X = 0 of the input (blue curve) and output (red curve) beams in (b) and (c), respectively. (e) Intensity profiles without (dash blue curve) and with (solid purple curves) hot spots along the horizontal direction across the five peak points in (b). (f) Intensity profiles without (dash blue curve) and with (solid purple curves) hot spots along the horizontal direction across the five peak points in (c).

Fig. 3. Output beam profiles without (a) and with (b) spectral clipping introduced by the limited grating size of G2. (c) Beam profiles at Y = 0 in (a) (red solid curve) and (b) (blue dashed curve) for the SSGP compressor, and the beam profiles output from G2 at Y = 0 without (green solid curve) and with (purple dashed curve) spectral clipping for a symmetric four-grating compressor. Spectral–spatial coupling profiles without (d) and with (e) spectral clipping. (f) The input spectrum (red solid curve) and the integrated output spectrum with spectral clipping (blue dashed curve). (g) Spectral profiles at positions 434 mm (solid curve), 217 mm (dashed curve) and 0 mm (dotted curve) away from the center on the left-hand side. (h) FTL temporal profiles at the same three positions, 434 mm (solid curve), 217 mm (dashed curve) and 0 mm (dotted curve). (i) FTL temporal profiles of the output spectrum without (red solid curve) and with (blue dashed curve) spectral clipping.

Fig. 4. Optical diagrammatic sketch of the SSGP-main-compressor-based MPC. PS_I, PS_II_X: prism pair system. DM_1, DM_2, DM_3: reflective deformable mirrors with different sizes. BE: beam expander and relay imaging systems. G1, G2: diffraction gratings. M1–M5: reflective mirrors. PM: parabolic reflective mirror. FP: focal point.

Fig. 5. Optical diagrammatic sketch for the wavefront aberration measuring and controlling of (a) DM_1, (b) DM_2 and (c) DM_3. DM_1, DM_2, DM_3: the reflective deformable mirrors corresponding to Figure 4. PM: parabolic reflective mirror.

Fig. 6. Intensity distributions in X–Z planes for beams without (a) and with 520 mm spatial chirp (b). (c) Intensity profiles at in (a) and (b), red solid curve for (a), blue solid curve for (b) and purple dashed curve for the difference between them.

Fig. 7. (1a) Near-field beam intensity without spatial chirp and spectral clipping. (1b)–(1d) Properties in the focal plane of the beam shown in (1a). (2a) Near-field beam intensity with 520 mm spatial chirp and spectral clipping. (2b)–(2d) Properties in the focal plane of the beam shown in (2a). (3a)–(3d) Intensity curves in the center along the horizontal axis of the figures above each one. The profiles in the X versus T, Y versus T and X versus Y planes are the projections in these planes of the spatial-temporal information in the focal plane.

Fig. 8. (a) Integrated temporal profiles in the focal plane in linear (a) and log (b), (c) scales, where the blue curve represents the ideal condition and the red curve represents the beam output from the SSGP compressor.

Fig. 9. Curves of the pulse duration at the focal point related to (a) the beam diameter, (b) the ratio of the spatial chirp region and (c), (d) the spectral bandwidth, at different induced spatial chirp widths (0, 60, 260, 520 mm) and beam sizes (500 and 860 mm), respectively.

Fig. 10. (a) Experimental setup of an SSGP main compressor; (b) spatial intensity modulations on the laser beam before G1; (c) output laser beam after the SSGP compressor; (d) temporal profiles at the focal point for single-pass and double-pass single-grating pairs; and (e) the spectral bandwidth of the input beam with a Gaussian profile.