Indirect and direct optical transitions in In{sub 0.5}Ga{sub 0.5}As/GaP quantum dots

Journal Article · Mon Mar 24 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4870087· OSTI ID:22258590

Sala, E. M.; Schliwa, A.; Strittmatter, A.; Bimberg, D. ^[1]; Selve, S. ^[2]; Niermann, T. ^[3]

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1. Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin (Germany)
2. Zentraleinrichtung Elektronenmikroskopie, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin (Germany)
3. Institut für Optik und Atomare Physik, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin (Germany)

We present a study of self-assembled In{sub 0.5}Ga{sub 0.5}As quantum dots on GaP(001) surfaces linking growth parameters with structural, optical, and electronic properties. Quantum dot densities from 5.0 × 10{sup 7} cm{sup −2} to 1.5 × 10{sup 11} cm{sup −2} are achieved. A ripening process during a growth interruption after In{sub 0.5}Ga{sub 0.5}As deposition is used to vary the quantum dot size. The main focus of this work lies on the nature of optical transitions which can be switched from low-efficient indirect to high-efficient direct ones through improved strain relief of the quantum dots by different cap layers.

• OSTI ID: 22258590
• Journal Information: Applied Physics Letters, Vol. 104, Issue 12; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CRYSTAL GROWTH
DEPOSITION
GALLIUM PHOSPHIDES
QUANTUM DOTS