Fig. 1: Experimental setup with simultaneous small- and wide-angle scattering measurements.
From: Dynamics of nanoscale phase decomposition in laser ablation
a Schematic of the femtosecond laser pump, X-ray FEL probe experiment. The samples are 100 nm thick Au films deposited on \({{\rm{S}}}{{{\rm{i}}}}_{3}{{{\rm{N}}}}_{4}\) membranes made from 4 in. silicon wafers. The wafer is mounted on translation stages for 2D rastering. The SAXS scattering pattern shown in the schematic is detected by one of the four ePix100s placed at small angles. A JungFrau-1M detector is used to capture the WAXS from the sample. At negative delays (\({{\rm{\delta}}} {{\rm{t}}} \, < \, 0\) ps), it captures Au (111) and Au (200) polycrystalline Bragg peaks from the film, as shown in the schematic. b A zoomed-in view of the cross-section of a membrane window. c The difference scattering pattern measured by all four ePix100 detectors. The small-angle images in a and c are measured at 250 ps after laser excitation at an incident laser fluence of 6.3 J/cm2.
