Functional materials and devices often exhibit enormous complexity in real space. Electron microscopy is routinely used in their development and testing, but the approach is usually limited to static and destructive imaging due thickness constraints and cross-talk of the electron probe. X-rays, by contrast, promise non-destructive, in-operando, 3D microscopy on materials and devices with a rich variety of contrast mechanisms. However, the challenge of such imaging experiments is that they require exceptional spatial and temporal resolution, often beyond the reach of established imaging techniques. In this context, coherent x-ray imaging offers unique opportunities to overcome technological and even apparently fundamental limits.

 

In this talk, I will introduce the method of coherent x-ray imaging, including the concept of phase retrieval, which allows to reconstruct a real-space image from x-ray scattering data. We will understand why the technique yields superior spatial resolution compared to conventional x-ray microscopy, and by which means it can even capture stochastic dynamics. Using this technique, we are able to observe the interaction of magnetic domain walls with magnetic pinning sites in space and time, and even quantify the micromagnetic energy behind such pinning. I will conclude with a perspective on the future of coherent imaging at upcoming light sources.