probed by time-resolved x-ray diffraction

Structural dynamics of 3OOps laser irradiated semiconductor is studied by means of picosecond time-resolved X-raydiffraction. Picosecond pulsed X rays are generated by focusing intense femtosecond laser beams onto metal target.Time-resolved X-ray diffraction is performed by a laser pump and X-ray probe technique. Lattice expansion due toacoustic phonon generation and propagation is observed in a silicon crystal in a single laser shot experiment at laserenergy density of 1.0 J/cm2. On the other hand, in a multiple laser shot experiment, lattice compression due to lasershock compression is observed at l4 J/cm2.Keywords: femtosecond laser, X-ray pulse, time-resolved X-ray diffraction, structural dynamics