It was noted that enhanced superlattice disordering in non-stoichiometric quantum wells exhibited a weak temperature dependence because of a decay of the supersaturated concentration of group-III vacancies. A formalism was presented for transient enhanced diffusion in non-stoichiometric materials. The migration enthalpy could be deduced from this by assuming that the vacancy decay was thermally activated. By analyzing electro-absorption from the quantum-confined Stark effect for a set of isochronal and isothermal annealing treatments, it was possible to extract a migration enthalpy of 1.8eV for group-III vacancies as well as an activation enthalpy of 0.7eV for vacancy annihilation.

Enhanced Diffusion in Nonstoichiometric Quantum Wells and the Decay of Supersaturated Vacancy Concentrations. I.Lahiri, D.D.Nolte, M.R.Melloch, J.M.Woodall, W.Walukiewicz: Applied Physics Letters, 1996, 69[2], 239-41