Ultrafast Dynamics

Ultrafast measurements of chemical reactions and phonon behavior have been carried out using time-resolve synchrotron radiation-based x-ray absorption, free-electron laser diffraction, as well as all-optical pump-probe experiments. Above is a plot of the time-dependence of a free-electron based optical-pump/ x-ray probe diffraction experiment on a Ge₂Sb₂Te₅ single epilayer (left) along with a simulation of the diffraction signal based upon the propagation of the acoustic phonon generated by the 20 fs optical pump pulse.