OPTICAL-ABSORPTION AND EXCITON LINEWIDTHS OF ZN(1-X)CD(X)SE QUANTUM-WELLS

Comparison of experimentally determined optical spectra of Zn1-xCdxSe/ ZnSe quantum wells with theoretical results for fundamental optical ab sorption and exciton linewidths is used to determine valence-band offs et and properties of exciton features as a function of well width and temperature. The heavy-hole valence-band offset is found to be approxi mately 90 meV for x = 0.23. The exciton linewidths are analyzed in ter ms of Gaussian inhomogeneous broadening attributable to expected sampl e inhomogeneities involving well widths and alloy concentrations and h omogeneous broadening associated with exciton-optical-phonon interacti ons. The linewidths are found to be smaller and larger than the bulk v alue for narrow (30 angstrom) and wide (200 angstrom) widths, respecti vely, in agreement with experimental results.