Modulated reflectivity spectrum of strained ZnSe/${\mathrm{Zn}}_{1\mathrm{-}\mathit{x}}$${\mathrm{Cd}}_{\mathit{x}}$Se/ZnSe single quantum wells

The piezo- and electromodulated spectra of ZnSe/${\mathrm{Zn}}_{0.84}$ ${\mathrm{Cd}}_{0.16}$Se/ZnSe single quantum wells, grown by molecular-beam epitaxy on (001) GaAs substrates, exhibit features associated with transitions between quantum confined levels. The transition energies are consistent with a theoretical model based on the k⋅p formalism and the transfer-matrix method. An unusually large (∼40 meV) heavy-hole–light-hole splitting is observed in these quantum wells. The theoretical model accounts for the large splitting in terms of the strain arising from the lattice mismatch between the layers forming the quantum well. An excitonic model has been used successfully to account for the line shape of the spectral features.