Effect of band hybridization on exciton states in GaAs-AlxGa1−xAs quantum wells

Binding energies and oscillator strengths of ground-state Wannier excitons in GaAs-${\mathrm{Al}}_{\mathrm{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathrm{x}}$As quantum wells are studied by a multiband effective-mass method. The present calculation incorporates valence-band nonparabolicity resulting from the hybridization of heavy and light holes. The variation of the exciton binding energy and oscillator strength as a function of the GaAs well width and the aluminum mole fraction of the ${\mathrm{Al}}_{\mathrm{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathrm{x}}$As barrier is discussed.