Impact of capping layer type on emission of InAs quantum dots embedded in InGaAs/In{sub x}Al{sub y}Ga{sub z}As/GaAs quantum wells

Journal Article · Tue Jan 07 00:00:00 EST 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4858456· OSTI ID:22271298

Casas Espinola, J. L. ^[1]; Stintz, A. ^[2]

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1. ESFM–Instituto Politécnico Nacional, México D. F. 07738, México (Mexico)
2. Center of High Technology Materials, University of New Mexico, Albuquerque, New Mexico 87106 (United States)

The optical and structural properties of In{sub 0.15}Ga{sub 0.85}As/In{sub x}Al{sub y}Ga{sub z}As/GaAs quantum wells with embedded InAs quantum dots (QDs) were investigated by the photoluminescence (PL), its temperature dependence, X-ray diffraction (XRD), and high resolution (HR-XRD) methods in dependence on the composition of capping In{sub x}Al{sub y}Ga{sub z}As layers. Three types of capping layers (Al{sub 0.3}Ga{sub 0.7}As, Al{sub 0.10}Ga{sub 0.75}In{sub 0.15}As, and Al{sub 0.40}Ga{sub 0.45}In{sub 0.15}As) have been used and their impact on PL parameters has been compared. Temperature dependences of PL peak positions in QDs have been analyzed in the range of 10–500 K and to compare with the temperature shrinkage of band gap in the bulk InAs crystal. This permits to investigate the QD material composition and the efficiency of Ga(Al)/In inter diffusion in dependence on the type of In{sub x}Al{sub y}Ga{sub z}As capping layers. XRD and HR-XRD used to control the composition of quantum well layers. It is shown that QD material composition is closer to InAs in the structure with the Al{sub 0.40}Ga{sub 0.45}In{sub 0.15}As capping layer and for this structure the emission 1.3 μm is detected at 300 K. The thermal decay of the integrated PL intensity has been studied as well. It is revealed the fast 10{sup 2}-fold thermal decay of the integrated PL intensity in the structure with the Al{sub 0.10}Ga{sub 0.75}In{sub 0.15}As capping layer in comparison with 10-fold decay in other structures. Finally, the reasons of PL spectrum transformation and the mechanism of PL thermal decay for different capping layers have been analyzed and discussed.

• OSTI ID: 22271298
• Journal Information: Journal of Applied Physics, Vol. 115, Issue 1; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM ARSENIDES
COMPARATIVE EVALUATIONS
CRYSTALS
DIFFUSION
EMISSION SPECTRA
GALLIUM ARSENIDES
HETEROJUNCTIONS
INDIUM ARSENIDES
LAYERS
PHOTOLUMINESCENCE
QUANTUM DOTS
QUANTUM WELLS
TEMPERATURE DEPENDENCE
X-RAY DIFFRACTION