Thermal and radiation-enhanced diffusion in Cu3Au

Thermal and radiation-enhanced diffusion in thin films of the order-disorde r alloy Cu3Au have been analyzed above and below the transition temperature . It is demonstrated that thin films grown by molecular beam epitaxy are un iquely suited for such experiments as the surface provides a dominant and w ell-characterized sink for migrating defects. The analysis is applied to re cent experiments. Quantitative predictions of radiation-enhanced diffusion agree closely with experimental values. Analysis of the tracer-impurity the rmal diffusion experiments provide host diffusion coefficients in a tempera ture regime through the transition temperature which were heretofore unavai lable. [S0163-1829(99) 13725-1].