Persistent template effect in InAs/GaAs quantum dot bilayers

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 si...

Full description

Saved in:
Bibliographic Details
Published in:Journal of applied physics 2010-06, Vol.107 (11), p.113502-113502-6
Main Authors: Clarke, E., Howe, P., Taylor, M., Spencer, P., Harbord, E., Murray, R., Kadkhodazadeh, S., McComb, D. W., Stevens, B. J., Hogg, R. A.
Format: Article
Language:English
Subjects:
ARSENIC COMPOUNDS
ARSENIDES
CRYSTAL GROWTH
CRYSTAL GROWTH METHODS
ENERGY RANGE
EPITAXY
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
INDIUM ARSENIDES
INDIUM COMPOUNDS
INTERFACES
LAYERS
MATERIALS
MATERIALS SCIENCE
MEV RANGE
MOLECULAR BEAM EPITAXY
NANOSCIENCE AND NANOTECHNOLOGY
NANOSTRUCTURES
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PNICTIDES
QUANTUM DOTS
SEMICONDUCTOR MATERIALS
TEMPERATURE DEPENDENCE
WAVELENGTHS
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary: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.
ISSN:0021-8979
1089-7550
DOI:10.1063/1.3429226