Magnetism in Pure and Doped Manganese clusters

摘要

We study pure and As-doped manganese clusters from density functional theory. Our results show excellent agreement with the SG molecular beam experiment. Introduction of a single As atom in Mn_x clusters enhances binding energies substantially. However, the Mn-Mn ferromagnetic coupling is found only in Mn_2As and Mn_4As clusters. We show the exchange coupling in these doped clusters behave quite differently from the RKKY-like predictions as cluster size increases. It's possible relevance to the Ⅲ-Ⅴ semiconductor is also discussed.