Synchrotron radiation - A versatile tool for diffusion studies

Due to the finite size, dynamical effects become more pronounced but also more complex in nanostructured materials compared to bulk solids. The progress in synchrotron methods and the access to X-rays of third generation synchrotron radiation sources enables studies of dynamics in surfaces and nanostructures. Especially nuclear resonant scattering of synchrotron radiation, which has gained the sensitivity required to study ultra thin films in the last years, can explore nearly the whole field of dynamical effects. Combining X-ray reflexion with nuclear resonant scattering of synchrotron radiation results in the depth-selective investigation of hyperfine parameters of the resonant atoms, allowing study their motion in near-surface layers. The availability of coherent X-rays enabled photon correlation spectroscopy studies of coarsening mechanisms in phase-separating alloys otherwise inaccessible with any other experimental method. The manuscript is intended as compact but extensive introduction into theoretical principles of synchrotron radiation methods applied for diffusion studies, illustrated with most recent experimental results.