Femtosecond Time-resolved X-ray Diffraction for Laser-excited CdTe Crystal

Abstract

Recent developments of high-power femtosecond laser system enable to generate the ultrashort X-ray pulses, which completely synchronize with the laser pulse. Time-resolved X-ray diffraction for laser-excited materials has been extensively performed [1]–[7]. Since the X-ray diffraction signal is sensitive to a change of lattice d-spacing with an accuracy of milliangstrom, this technique is ideal for measuring the rapid and small changes in crystal structures. Recently, Sokolowski-Tinten et al. [8] measured the longitudinal coherent optical phonon in semimetal (Bi) using ultrafast X-ray diffraction with a new analysis. This technique was performed to detect. Time-resolved X-ray diffracted signal taking within a much shorter period than the oscillation of coherent phonon showed alteration of its intensity due to the coherent atomic deviation from the crystallographic atomic position. In this paper, we performed femtosecond time-resolved X-ray diffraction (FTXRD) to detect the coherent optical phonon in CdTe (111) single crystal.