Optical observation of quantum-dot formation in sub-critical CdSe layers grown on ZnSe
نویسندگان
چکیده
The evolution of CdSe quantum dot (QD) formation on ZnSe was investigated on a series of samples grown by MBE, with nominal CdSe coverages ranging from 1.1 to 2.6 monolayers (ML). Micro-PL data suggest strongly con"ned zero-dimensional excitons even for coverages as low as 1.1 ML. PL and micro-PL data show emission from the QDs as well as from an accompanying 2 D layer; the temperature dependence of these emissions is notably di!erent. Strong red-shifts of both emissions as the CdSe coverage increases are observed. ( 2000 Elsevier Science B.V. All rights reserved. PACS: 78.66.Hf; 78.66.!w; 78.55.Et; 68.65.#g; 81.15.Hi
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