Observation of the excited level of excitons in GaAs quantum wells

Abstract

The light- and heavy-hole two-dimensional exciton term values are determined directly from the excitation spectra of GaAs-${\mathrm{Al}}_{x}{\mathrm{Ga}}_{1\ensuremath{-}x}\mathrm{As}$ heterostructures with GaAs well widths $L$ from 42 to 145 \AA{}. these values are in excellent agreement with a theoretical model which contains no adjustable parameters. This theory also gives integrated strengths for the excitons which agree with experiment, and ground-state binding energies as a function of $L$.