Positron-Annihilation Spectroscopy of Vacancy Defects in Aluminum

摘要

Positron-annihilation characteristics in a monovacancy and a divacancy in aluminium have been calculated self-consistently using a local density functional formalism, into which the many-body enhancement effects have been incorporated. Results for the theoretical two-dimensional angular correlation of annihilation radiation spectra are compared to experimental results obtained from an aluminum single crystal at 20 exp 0 C, where positrons annihilate from a Bloch-state, and at higher temperatures, 500 exp 0 C and 630 exp 0 C, where they annihilate primarily from vacancy-trapped states. (ERA citation 08:023939)