The exciton properties of self-assembled rectangular and V-shaped quantum wires are investigated theoretically in the presence of a magnetic field. The calculations are done in the single band effective mass approximation. We study the diamagnetic shift, the influence of the electron-hole Coulomb interaction, as well as the electronic properties and the photoluminescence peak energies for magnetic fields applied along and perpendicular to the wire. The results are compared with available magneto-photoluminescence experimental measurements.

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The magnetic field dependence of the excitonic states in unstrained GaAs/ Al x Ga 1−x As quantum dots is investigated theoretically and experimentally. The diamagnetic shift for the ground and the excited states are studied in magnetic fields of varying orientation. In the theoretical study, calculations are performed within the single band effective mass approximation, including band nonparabolicity, the full experimental threedimensional dot shape and the electron-hole Coulomb interaction. These calculations are compared with the experimental results for both the ground and the excited states in fields up to 50 Tesla. Good agreement is found between theory and experiment.

Charge confinement in InAs/ InP self-assembled quantum wires is studied experimentally using photoluminescence in pulsed magnetic fields and theoretically using adiabatic theory within the effective-mass approximation, taking into account the strain in the samples. We show both experimentally and theoretically that, in spite of the large conduction band offset, the electron wave function is significantly spilled out of the wire in the wire height direction for thin wires. Furthermore, for a wire thickness of up to 8 monolayers, the electron spillover is inversely related to the wire height. These effects are due to the large zero point energy of the electron. As the wire becomes thicker, the decrease in confinement energy is reflected in a reduction of the electron wave-function extent.

The binding energy for charged excitons ͑X − and X + ͒ is calculated within the single-band effective mass approximation including effects due to strain for rectangular, triangular, and V-shaped quantum wires. Both X − and X + are found to be bound in rectangular InAs/ InP quantum wires and V-shaped GaAs/ Al 0.32 Ga 0.68 As quantum wires. We found an appreciable dependence of the trion binding energy on the size and shape of the quantum wire. We compare with available experimental data.