Observation of spin-triplet states for double donors in silicon

Abstract

By the application of uniaxial stress, an allowed optical transition of chalcogen donors in silicon can be brought into near resonance with a forbidden transition. If the interaction coupling the two final states is strong enough, both transitions will become visible in absorption. We report here the first study of spin-triplet states of double donors, and our results indicate that many-electron effects are substantial in these systems.