Persistent template effect in InAs/GaAs quantum dot bilayers

Journal Article · Tue Jun 15 00:00:00 EDT 2010 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3429226· OSTI ID:21476285

Clarke, E; Howe, P; Taylor, M; Spencer, P; Harbord, E; Murray, R ^[1]; Kadkhodazadeh, S; McComb, D W ^[2]; Stevens, B J; Hogg, R A ^[3]

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1. Department of Physics, Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2AZ (United Kingdom)
2. Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom)
3. School of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)

The dependence of the optical properties of InAs/GaAs quantum dot (QD) bilayers on seed layer growth temperature and second layer InAs coverage is investigated. As the seed layer growth temperature is increased, a low density of large QDs is obtained. This results in a concomitant increase in dot size in the second layer, which extends their emission wavelength, reaching a saturation value of around 1400 nm at room temperature for GaAs-capped bilayers. Capping the second dot layer with InGaAs results in a further extension of the emission wavelength, to 1515 nm at room temperature with a narrow linewidth of 22 meV. Addition of more InAs to high density bilayers does not result in a significant extension of emission wavelength as most additional material migrates to coalesced InAs islands but, in contrast to single layers, a substantial population of regular QDs remains.

• OSTI ID: 21476285
• Journal Information: Journal of Applied Physics, Vol. 107, Issue 11; Other Information: DOI: 10.1063/1.3429226; (c) 2010 American Institute of Physics; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
CRYSTAL GROWTH
GALLIUM ARSENIDES
INDIUM ARSENIDES
INTERFACES
LAYERS
MEV RANGE
MOLECULAR BEAM EPITAXY
OPTICAL PROPERTIES
QUANTUM DOTS
SEMICONDUCTOR MATERIALS
TEMPERATURE DEPENDENCE
WAVELENGTHS
ARSENIC COMPOUNDS
ARSENIDES
CRYSTAL GROWTH METHODS
ENERGY RANGE
EPITAXY
GALLIUM COMPOUNDS
INDIUM COMPOUNDS
MATERIALS
NANOSTRUCTURES
PHYSICAL PROPERTIES
PNICTIDES