CdSe quantum dots in a Zn 1 ~ x Mn x Se matrix : new e ! ects due to the presence of Mn
نویسنده
چکیده
We report detailed photoluminescence (PL) and magneto-PL data on a new II}VI quantum dot (QD) system involving diluted magnetic semiconductors (DMSs). CdSe dots embedded in ZnMnSe exhibit relatively weak PL emission compared to analogous non-DMS systems, such as CdSe/ZnSe. However, we observe a dramatic increase in the PL intensity emitted by excitons con"ned in such QDs when a magnetic "eld is applied. We explain this e!ect in terms of an e$cient transfer of excitation between the excitons and the Mn ions. In addition to this, we report on the role that Mn plays in CdSe dot nucleation, providing a new handle for optimization of the growth of the CdSe QDs. ( 2000 Elsevier Science B.V. All rights reserved. PACS: 78.66.Hf; 78.66.!w; 75.70.Ak; 78.20.Ls; 78.55.Et; 81.15.Hi
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