Abstract
Femto- and picosecond X-rays and electrons can be generated and used at the Femtosecond Ultrafast Quantum Phenomena Research Facility in Nuclear Engineering Research Laboratory, University of Tokyo. The beams are mainly applied to pump-and-probe analysis. The analysis utilizes two synchronized ultrashort beams. Especially, the time-resolved X-ray diffraction, which is one of the analysis, enables the dynamic visualization of atomic motions. Visualized atomic motions in coherent phonon, phase relaxation, phase transition, thermal expansion and shock wave in GaAs monocrystal irradiated by a femtosecond laser are described in this paper.
