Seminars Archive

Thu 14 Mar, at 10:00 - Seminar Room T1

Driven material dynamics studied with free electron laser

Klaus Sokolowski-Tinten
Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen

Ultrafast pulsed excitation of solids allows to create states of strong electronic excitation and high temperature and pressure. Subsequent to the initial deposition of energy a complex chain of secondary relaxation processes can lead to structural changes on very rapid time-scales, and often along unusual, non-equilibrium pathways. These processes have attracted continuing interest for more than three decades, both from a fundamental physics viewpoint as well as with respect to technological applications such as laser-processing and material synthesis. In this contribution I will present examples from our work where we have used the intense, short-pulse and short-wavelength radiation of free electron lasers to probe the transient response of strongly driven materials at the relevant length (i.e. Å to nm) and time (i.e. fs to ps) scales. This includes studies of fs laser-induced melting (both thermal and non-thermal), phase transition dynamics in phase change materials, short pulse laser ablation, and nanoscale structure formation (i.e. ripples) at laser-irradiated surfaces.

(Referer: D. Fausti)
Last Updated on Tuesday, 24 April 2012 15:21