KeV x-ray source toward 100 fs time-resolved X-ray applications

摘要

Optical pump, x-ray diffraction probe experiments have been used to study the lattice dynamics of organic materials using a laser-produced plasma x-ray source. The plasma x-ray source is generated from a 10 Hz, 26 mJ, 120 fs laser beam focused on a silicon wafer target. The emitted K_α x-ray radiation is used to probe samples optically perturbed at laser fluences from 1.8 J/cm~2 to 27 J/cm~2. Ultrafast disordering inside the lattice - within a time scale below 600 fs to few tens of picoseconds - is clearly observed and produce a drop of the probe x-ray diffracted signal.