Time Domain Study of57Fe Diffusion using Nuclear Forward Scattering of Synchrotron Radiation

Diffusion of ${}^{57}\mathrm{Fe}$ in the intermetallic alloy ${\mathrm{Fe}}_3\mathrm{Si}$ was investigated using nuclear forward scattering of synchrotron radiation parallel to the [113] crystal direction with the aim to demonstrate the feasibility of a diffusion study in a crystalline solid. The jumps between different sites on a lattice, corresponding to a finite residence time on one and the same lattice site, cause a loss of coherence of scattered synchrotron radiation. This gives rise to a decay of the forward scattered intensity which is faster than under static conditions. From the time dependence of the decay diffusivities of iron are derived.