Electronic structure of superlattices of II-VI/III-V diluted magnetic semiconductors

The possibility controlling the magnetism of III-V /II-VI superstructures of the diluted magnetic semiconductor AlAs/(Cd,Mn)Te is investigated by use of the KKR-CPA-LDA (Korringa-Kohn-Rostoker coherent-potential approximation and the local density approximation) first principles calculation. The superlattice whose unit cell is composed of a single AlAs layer and a single CdMnTe layer becomes ferromagnetic when the number of carrier holes are increased. In the case where the number of the CdMnTe layer in the unit cell is increased, the interlayer coupling between the CdMnTe layers becomes antiferromagnetic because the carrier holes reside only at the III-V /II-VI heterosurfaces.