Abstract
We have investigated the optical properties of InAs/GaAs (113)A quantum dots grown by molecular beam epitaxy (MBE) capped by (In,Ga)As. Reflection high‐energy electron diffraction (RHEED) is used to investigate the formation process of InAs quantum dots (QDs). A broadening of the PL emission due to size distribution of the dots, when InAs dots are capped by GaAs, was observed. A separation between large and small quantum dots, when they are encapsulated by InGaAs, was shown due to hydrostatic and biaxial strain action on large and small dots grown under specifically growth conditions. The PL polarization measurements have shown that the small dots require an elongated form, but the large dots present a quasi‐isotropic behavior.
Highlights
Self-assembled quantum dots (QDs) have been studied intensively for more than a decade due to their unique physical properties arising from the three-dimensional quantum confinement of carriers and delta-like density of state [1,2,3]
It is known that the growth of InGaAs layer on InAs quantum dots, developed on (001) GaAs substrates, reduces the stress in quantum dots due to the decrease of hydrostatic strain
A broadening of the PL emission due to size distribution of the dots, when InAs dots are capped by GaAs, is observed
Summary
Self-assembled quantum dots (QDs) have been studied intensively for more than a decade due to their unique physical properties arising from the three-dimensional quantum confinement of carriers and delta-like density of state [1,2,3]. One way to improve or adjust the QDs properties is the utilization of high-index substrates which exhibit some interesting phenomena, with respect to (001) orientation. There are few reports about successful growth of self-organized QDs on high-index substrates, comparable to those with (001) orientation [6, 7]. The growth control and the valid results, obtained on these structures, which are elaborated on high-index substrates, have permitted to improve optical and electrical properties of many compounds [9, 10]. Prior to understanding how the capping layer influences the transition energies of [11 k] grown InAs QDs, one has to know the effect on the transition energies of QD growth on [11 k] substrates (k = 1, 2, 3). We explained the effects of the hydrostatic and biaxial strain on the transition energy when the dots are encapsulated by InGaAs layer
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
