Fachgruppe Nanostrukturierte Materialien |
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Institut f. Physik
Tel.: +49 345 55 25321 |
E. Margapoti, L. Worschech, S. Mahapatra, T. Slobodskyy, A. Tribu, T. Aichele, K. Brunner, G. Schmidt, L.W. Molenkamp, R. André, K. Kheng, C. Bougerol, A. Forchel Optical characterization of thermally annealed self-assembled ZnCdSe quantum dots Phys. Stat. Soli. (C) Current Topics in Solid State Physics 4 (9) (2015-02-24 13:49:51), 3280-3288 Post-growth thermal annealing, (TA) in combination with mesa-fabrication technologies, was applied to tune the shape and material composition of ZnCdSe quantum dots (QDs). The QDs were studied by means of photoluminescence spectroscopy. An enhancement of QD homogeneity due to TA is demonstrated by substantial narrowing of the QD emission, observed from large QD ensembles. Energy shifts of QD luminescence, exceeding 100 meV after thermal annealing, were observed. Tracing the evolution of single exciton lines, the activation energy of an enhanced diffusion process in small mesas was determined. Distinct changes of quantum dot symmetries were identified through a reduction of the exciton fine structure splitting. http://onlinelibrary.wiley.com/doi/10.1002/pssc.200775411/abstract |