Temperature dependence of exciton localization in Zn1-xCdxSe quantum wells

We report the results of the investigation of the temperature dependence of the spontaneous emission of localized excitons in Zn1-xCdxSe quantum wells (QWs). Two main peaks, which show a strong change in relative intensities with temperature, dominate the spectra, The presence in the spectra of biex citons and bound excitons was ruled out after the corresponding analyses. C alculation of the fundamental transitions of the QWs suggested that the pea ks are due to thickness fluctuations of one and two monomolecular layers. T he successful analysis of the spectra in terms of a simple two-level model indicated that localization of excitons due to QW thickness fluctuations an d exciton migration are basic processes which have noticeable;influence in the spontaneous emission of Zn1-xCdxSe QWs. (C) 2000 American Vacuum Societ y.