Excitons in diluted magnetic semiconductor quantum wires

As a consequence of a confinement in two spatial directions and due to the presence of p–d exchange interaction, a relative contribution of the heavy- and light-hole components of the ground state of a hole in a diluted magnetic semiconductor quantum wire depends strongly on an external magnetic field. In particular, this fact leads to a magnetic field dependence of along-the-wire effective mass of the space-quantized holes and, consequently, to a magnetic field dependence of the exciton binding energy. Numerical calculations performed for T-shaped Cd1−x−yMnxMgyTe/Cd1−xMnxTe quantum wire structures clearly demonstrate this additional dependence of the exciton binding energy on the magnetic field.