FIG. 3.

Amplitude dynamics of the PLD obtained from main lattice reflexes. (a) Time-dependent intensity of visible main lattice reflexes and integrated background intensity, for a fluence of $F=3.8$ mJ/cm². Two inequivalent classes of spot groups are found, featuring a strong (dark blue) and a weak (light blue) sensitivity to the amplitude quench. (b) Sketch of the IC diffraction pattern, and parts of the difference diffraction image ($I_{t=1\text{ps}}-I_{t<0}$) around the (10) and (01) main reflexes (insets). (c) Schematic comparison of peak intensities in the spot groups. The red area highlights different sensitivities to the PLD. (d) Extracted PLD amplitude quench and relaxation (see also Appendix A) for three fluences, showing a rapid and a slower relaxation component (time constants from a biexponential fit (black line) to the highest fluence data: (2.8 ± 0.3) ps and (96 ± 3) ps).