Utilization of high speed x‐ray topography for determining diffusion coefficients of point defects in nearly perfect crystals

A new method for determining diffusion coefficients of point defects using synchrotron radiation topography (SRT) is described. Since the method is based on dynamical observations of dislocation motion in a thick specimen with a low dislocation density, advantage of the SRT is fully utilized. It is shown by typical observations on ice crystals that an absolute value of the diffusion coefficient is determined by a simple analysis of the climb motion of the dislocations.