Dislocation core and pipe diffusion in Y₂O₃

Little is known about the dislocation core and the related pipe diffusion in oxides. Interesting features can be gained from irradiation induced defect nucleation along dislocation lines. In yttrium sesquioxide Y2O3, it is observed that the pipe diffusion is the driving force of nucleation of extended defects which involves the diffusion of both ions, metal and oxygen. A periodic distribution of defects along the dislocation is interpreted in terms of dislocation core instability based on the effect known as Rayleigh instability.