Valence-band states in diluted magnetic-semiconductor quantum wires

We present a theoretical study of the valence-band states in diluted magnet ic semiconductor quantum wire structures. As a consequence of confinement i n two directions, the hole states in a quantum wire are known to be mixture s of heavy- and light-hole components. Due to a strong p-d exchange interac tion in diluted magnetic semiconductors, the relative contribution of these components is strongly affected by an external magnetic field B, a feature that is absent in nonmagnetic quantum wires. This leads, in turn, to a str ong magnetic-field dependence of the probabilities of various optical dipol e transitions in diluted magnetic semiconductor quantum wires. Numerical ca lculations performed for the case of Cd1-xMnxTe/Cd1-x-yMnxMg gamma Te T-sha ped quantum wires demonstrate the possibility to efficiently control the po larization characteristics of light emitted from such structures by means o f an external magnetic field B.