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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Atomically resolved study of the morphology change of InAs/GaAs quantum dot layers induced by rapid thermal annealing

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Keizer, J. G. [1] ; Henriques, A. B. [2] ; Maia, A. D. B. [2] ; Quivy, A. A. [2] ; Koenraad, P. M. [1]
Total Authors: 5
[1] Eindhoven Univ Technol, Dept Appl Phys, NL-5600 MB Eindhoven - Netherlands
[2] Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo - Brazil
Total Affiliations: 2
Document type: Journal article
Source: Applied Physics Letters; v. 101, n. 24 DEC 10 2012.
Web of Science Citations: 7

The optoelectronic properties of InAs/GaAs quantum dots can be tuned by rapid thermal annealing. In this study, the morphology change of InAs/GaAs quantum dots layers induced by rapid thermal annealing was investigated at the atomic-scale by cross-sectional scanning tunneling microscopy. Finite elements calculations that model the outward relaxation of the cleaved surface were used to determine the indium composition profile of the wetting layer and the quantum dots prior and post rapid thermal annealing. The results show that the wetting layer is broadened upon annealing. This broadening could be modeled by assuming a random walk of indium atoms. Furthermore, we show that the stronger strain gradient at the location of the quantum dots enhances the intermixing. Photoluminescence measurements show a blueshift and narrowing of the photoluminescence peak. Temperature dependent photoluminescence measurements show a lower activation energy for the annealed sample. These results are in agreement with the observed change in morphology. (C) 2012 American Institute of Physics. {[}] (AU)

FAPESP's process: 10/10452-8 - Multiple harmonic spectroscopy, spin orientation and instantaneous magnetization using light
Grantee:Andre Bohomoletz Henriques
Support type: Regular Research Grants