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 biexcitons and bound excitons was ruled out after the corresponding analyses. Calculation of the fundamental transitions of the QWs suggested that the peaks are due to thickness fluctuations of one and two monomolecular layers. The successful analysis of the spectra in terms of a simple two-level model indicated that localization of excitons due to QW thickness fluctuations and exciton migration are basic processes which have noticeable;influence in the spontaneous emission of Zn1-xCdxSe QWs. (C) 2000 American Vacuum Society.