Dark Field X-ray Microscopy — Multiscale Microscopy, Microstructures, Models, Magnetism and More
Abstract: In this talk, I will present the status on Dark Field X-ray Microsocpy, DFXM, as developed at ID06 at ESRF. The method allows acquiring 3D movies of grains, domains and defects in mm sized crystalline specimens and the associated evolution of local strain. Kinematical scattering and wavefield propagation methods will be presented that enables direct interfacing of such data with 3D multiscale micro-mechanical models. I will comment on contrast mechanisms and current limitations. As a main example of use I will present in situ studies of dislocation and domain evolution during plastic deformation of pure metals, and discuss how such data may be interfaced to multiscale modelling. Plans for the new dedicated beamline ID03 at ESRF are summarized.
Next, I will outline DFXM work in new directions. As a demonstration of DFXM with a time resolution of ps resolution, I present the visualization of acoustic waves propagating in diamond by means of a pump-probe scheme at LCLS. For improved spatial resolution, I will discuss perspectives for coupling with coherence based methods. Finally, in relation to the establishment of DFXM at 6-ID at APS, I will suggest a possible application of DFXM within magnetism.
Bio: Henning Friis Poulsen is a professor at the Physics Department of the Technical University of Denmark. His research interest is at the crossroad between x-ray and neutron physics, crystallography and multiscale materials science (metals, energy materials).