Abstract
The kinetics of annealing evaporated GeSe2 films is investigated through measurements on the optical-absorption edge. The data are found to follow a second-order rate equation. This is understood in terms of Se-atom diffusion through a process involving the excitation and diffusion of close valence-alternation pairs. The explanation is proposed to apply also to pnictide- and oxide-containing glasses and justifies the miniscule diffusion rate found in all of them.