Photoluminescence from seeded three-dimensional InAs∕GaAs quantum-dot crystals
2006; American Institute of Physics; Volume: 88; Issue: 4 Linguagem: Inglês
10.1063/1.2168494
ISSN1520-8842
AutoresSuwit Kiravittaya, Armando Rastelli, Oliver G. Schmidt,
Tópico(s)Semiconductor Lasers and Optical Devices
ResumoWe investigate the photoluminescence (PL) properties of three-dimensional InAs∕GaAs quantum-dot (QD) crystals grown on shallow modulated periodic hole arrays patterned on GaAs(001). We find that the PL spectra become narrower and more intense with increasing number of QD layers. A deconvoluted PL linewidth of 14.9 meV is obtained from a defect-free QD crystal consisting of 11 stacked QD layers. The PL spectra obtained for QD crystals containing QD vacancies show significantly broader spectra. The PL peak energy and linewidth of the QDs across the whole pattern (100×100μm2) remain constant within 1.278±0.001eV and 21.0±1.7meV, respectively. From power-dependent PL measurement, we can resolve up to seven excited-state PL peaks confirming the remarkable size homogeneity of our QD crystals. This experimental result can be reasonably fitted by a calculation based on random population theory and on a simple model for the QD confinement potential.
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