The photoluminescence (PL) and PL excitation (PLE) spectra of CdTe/ZnTe asymmetric double quantum well (QW) structures are studied on a series of samples containing two CdTe layers with nominal thicknesses of 2 and 4 monolayers (ML) in the ZnTe matrix. The samples differ in the thickness of the ZnTe spacer between CdTe QWs which is 45, 65 and 75 ML. It has been found that at above-barrier excitation the PL from a shallow QW at sufficiently weak excitation intensities is determined by recombination of hot excitons. It is shown that under these conditions, when PL is excited by lasers with different wavelengths, the ratio of the PL intensities from shallow and deep QWs decreases exponentially with an increase of the initial kinetic energy of hot excitons. It is found that energy relaxation of hot excitons with LO phonon emission determine the shape of the PLE spectrum of shallow QW in the range of exciton kinetic energies up to more than 20 LO phonons above ZnTe bandgap. We have shown that the results obtained are well described by the model of charge and energy transfer between QWs.
Original languageEnglish
Article number117762
Number of pages5
JournalJournal of Luminescence
Volume230
Early online date12 Nov 2020
DOIs
StatePublished - 1 Feb 2021

    Research areas

  • Asymmetric double quantum wells, Cadmium telluride, Zinc telluride, photoluminescence, Hot exciton relaxation, Photoluminescence, RAMAN-SCATTERING, RESONANCE, OPTICAL-PROPERTIES, BINDING-ENERGIES, DOTS, BEHAVIORS

    Scopus subject areas

  • Condensed Matter Physics
  • Chemistry(all)
  • Atomic and Molecular Physics, and Optics
  • Biophysics
  • Biochemistry

ID: 70928264