Abstract
We determine the effective total spin of local moments formed from acceptor states bound to Mn ions in GaAs by evaluating their magnetic Chern numbers. When individual Mn atoms are close to the sample surface, the total spin changes from to , due to quenching of the acceptor orbital moment. For Mn pairs in bulk, the total depends on pair orientation in the GaAs lattice and on the separation between the Mn atoms. We point out that Berry curvature variation as a function of local moment orientation can profoundly influence the quantum-spin dynamics of these magnetic entities.
- Received 21 July 2010
DOI:https://doi.org/10.1103/PhysRevLett.106.017202
© 2011 The American Physical Society