3D visualization of defects in diamond by Dark-Field X-ray Microscopy using an X-ray Free Electron Laser

Extended lattice displacements are ubiquitous in crystals, but notoriously difficult to resolve at their native femtosecond to nanosecond timescales. Conventional high spatial and reciprocal space resolution microscopy is ideal for some systems, but for bulk systems and ultrafast probing, novel types of microscopy are being developed. Dark Field X-ray Microscopy (DFXM) has the ability to achieve high spatial resolution (30-150 nm) and simultaneously high reciprocal space resolution(10-5). Originally developed at the synchrotron, recent advancements have led to the development of DFXM at XFEL sources, allowing for ultrafast pump-probe imaging experiments. In this talk, I will present our group's novel scan methodologies developed at the European XFEL that enable us to visualize long-range defects in three spatial dimensions and to characterize the rotational and axial strain fields produced by these defects. I will illustrate how the use of the fs-pulse-duration XFELs offers opportunities to resolve ultrafast structural dynamics. I also observe the effect of a propagating phonon wavepacket affects the line dislocation in a diamond sample, illustrating opportunities for new directions with these novel capabilities.