First-principles study of carrier-spin exchange interaction in (III,Mn)V and (II,Mn)VI diluted magnetic semiconductors

We investigated the electronic structures and the p-d and s-d exchange interaction between carriers and spins of (II,Mn)VI, and (III,Mn)V diluted magnetic semiconductors through first-principles pseudopotential total-energy calculations. We found that some macroscopic parameters, such as the energy separation of Mn-d band to band edge of a host semiconductor, lattice constant, the Phillips ionicity and the characteristics of valence band edge, determine the strength of the p-d exchange integral. We finally propose a model which explains the trend of the p-d exchange constant with these macroscopic parameters.