Cálculo modelo da superfície GaN(111): relaxações e defeitos nativos

Abstract

The success of crystaline GaN as an eletronic and optical has motivated enormous theoretical and experimental efforts in recent years in order to understand its properties. In this work we report a quantitative theory of the GaN (111) surface relaxed according several models and of native defects. We are concemed with the vacancies (V and Vn) and the anti-site defects (N and Gan) as bonded on the uppermost atomic layer. Our approach is to use total energy abinitio model calculations of planar molecular clusters of sizes ranging from 1x1 to 6x6 Ga3N3 units. We follow the convergence of the surface eletronic states, atomic charges, density of states, as a function of the molecular cluster'size.