Ultrafast Probes of Nanoscale Heterogeneous Dynamics

Presenter: Aaron Lindenberg, Stanford and SLAC National Accelerator Laboratory

Whereas it is fairly straightforward using current ultrafast x-ray and electron scattering techniques to capture coherent atomic-scale dynamics  at the unit cell level via crystallographic approaches, the dynamic disorder, heterogeneity, and fluctuations that occur during materials switching events remain largely mysterious.  Here I will describe recent efforts to probe such dynamic atomic-scale responses using two examples: In the hybrid perovskites I will show how transient diffuse scattering approaches enable a new understanding of local nanoscale polaronic distortions and the fundamental processes that accompany absorption of a photon.  I will also describe recent efforts using single-shot pump-probe x-ray photon correlation spectroscopy to visualize fundamental nucleation processes during the formation of a new light-induced metastable structure.