Speaker: Ilana Porter, Berkeley
Program Description:
Ultrafast spectroscopy has improved our understanding of the photoinitiated processes that occur in solar energy materials, such as thermalization, carrier localization, and transport. But previous optical techniques lack the elemental, oxidation state, and electron/hole specificity needed to solve the problems facing modern solar materials and devices. In this talk, I will describe how XUV transient absorption spectroscopy can be used to answer these questions in four model nanomaterial systems. We will explore charge transport across layers of a thin-film junction, electron small polaron trapping in oxide nanorods, a phonon bottleneck in silicon nanoparticles, and ultrafast hole localization in ferroelectric films.