The binding energies of excitons in quantum-well wires of GaAs surrounded by ${\mathrm{Ga}}_{1\mathrm{-}\mathrm{x}}$${\mathrm{Al}}_{\mathrm{x}}$As are calculated with the use of variational solutions to the effective-mass equation. The results we obtained show that the energies are dramatically dependent on the sizes of the wire, and also that their magnitudes are greater than those in comparable quasi-two-dimensional quantum-well structures.

• Received 12 February 1987

DOI:https://doi.org/10.1103/PhysRevB.35.9345