Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1616238 | Journal of Alloys and Compounds | 2012 | 6 Pages |
Abstract
The extended X-ray absorption fine structure (EXAFS) and diffraction anomalous fine structure (DAFS) have been applied to investigate a local structure for the CdSe/ZnSe quantum dots grown by molecular beam epitaxy (MBE) and migration-enhanced epitaxy (MEE). The aim was to study the intermixing of Cd and Zn atoms, chemical compositions and strain induced by cap-layer. The EXAFS at the Cd K-edge and DAFS at the Se K-edge proved the intermixing of Cd and Zn atoms. The distances Cd-Se (2.61Â Ã
) found from EXAFS and DAFS analysis for h1 region is closer to that in bulk CdSe (2.62Â Ã
). The DAFS analysis revealed the differences in the local structure in two investigated regions (i.e. different iso-strain volumes) on the quantum dots. It was found that the investigated areas differ in the Cd concentration. To explain the experimental results the theoretical calculation based on a full valence-force field (VFF) model was performed. The theoretical VFF model fully explains the experimental data.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
E. Piskorska-Hommel, V. Holý, O. Caha, A. Wolska, A. Gust, C. Kruse, H. Kröncke, J. Falta, D. Hommel,