Abstract
Localization of exciton wavefunctions in self-assembled quantum dots (QDs) has been investigated using CdSe QDs embedded in ZnMnSe. This system was chosen so as to make use of the giant Zeeman splitting in the diluted magnetic semiconductor (DMS) ZnMnSe, which enables one to map how the exciton wavefunction is distributed between the QDs and the surrounding matrix. Two series of CdSe QDs in ZnMnSe were prepared for this investigation by molecular beam epitaxy (MBE), either by varying the CdSe coverage while keeping a constant Mn concentration in ZnMnSe; or by varying the Mn concentration in the matrix while maintaining a constant CdSe coverage. Photoluminescence (PL) experiments show a systematic evolution of the CdSe QDs with increasing CdSe coverage; and also reveal the role of Mn in nucleating ("seeding") the self-assembly of the QDs. By simultaneously measuring the Zeeman shifts of the PL peaks from both the CdSe QDs and their ZnMnSe matrix, we are able to extract information on exciton localization in the QDs and its dependence on the degree of development of the self-assembled CdSe QDs with increasing CdSe coverage.
Original language | English |
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Pages (from-to) | 311-315 |
Number of pages | 5 |
Journal | Solid State Communications |
Volume | 141 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2007 Feb |
Bibliographical note
Funding Information:This research was supported by NSF Grants DMR02-45227; by a Korea Research Foundation Grant (KRF-2004-005-C00068); by KOSEF through QSRC at Dongguk University; and by the Seoul R&BD Program.
Keywords
- A. Magnetic semiconductor
- A. Quantum dot
- E. Zeeman mapping
ASJC Scopus subject areas
- General Chemistry
- Condensed Matter Physics
- Materials Chemistry