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Related papers: Understanding Polarization Properties of InAs Quan…

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III-V growth and surface conditions strongly influence the physical structure and resulting optical properties of self-assembled quantum dots (QDs). Beyond the design of a desired active optical wavelength, the polarization response of QDs…

We report on a atomistic theory of electronic structure and optical properties of a single InAs quantum dot grown on InP patterned substrate. The spatial positioning of individual dots using InP nano-templates results in a quantum dot…

Materials Science · Physics 2009-11-11 Weidong Sheng , Pawel Hawrylak

Recent experimental measurements, without any theoretical guidance, showed that isotropic polarization response can be achieved by increasing the number of QD layers in a QD stack. Here we analyse the polarization response of multi-layer…

Materials Science · Physics 2011-09-26 Muhammad Usman , Tomoya Inoue , Yukihiro Harda , Gerhard Klimeck , Takashi Kita

Tailoring electronic and optical properties of self-assembled InAs quantum dots (QDs) is a critical limit for the design of several QD-based optoelectronic devices operating in the telecom frequency range. We describe how a fine control of…

Mesoscale and Nanoscale Physics · Physics 2015-06-18 Vittorianna Tasco , Muhammad Usman , Milena De Giorgi , Adriana Passaseo

A detailed theoretical study of the optical absorption in self-assembled quantum dots is presented in this paper. A rigorous atomistic strain model as well as a sophisticated electronic band structure model are used to ensure accurate…

This study compares cross-sectional scanning tunnelling microscopy (XSTM) and atom probe tomography (APT). We use epitaxially grown self-assembled InAs quantum dots (QDs) in GaAs as an exemplary material with which to compare these two…

Materials Science · Physics 2015-05-20 A. D. Giddings , J. G. Keizer , M. Hara , G. J. Hamhuis , H. Yuasa , H. Fukuzawa , P. M. Koenraad

We adopt an atomistic pseudopotential description of the electronic structure of self-assembled, lens shaped InAs quantum dots within the ``linear combination of bulk bands'' method. We present a detailed comparison with experiment,…

Materials Science · Physics 2009-10-31 A. J. Williamson , L. W. Wang , Alex Zunger

The design of some optical devices such as semiconductor optical amplifiers for telecommunication applications requires polarization-insensitive optical emission at the long wavelengths (1300-1550 nm). Self-assembled InAs/GaAs quantum dots…

Materials Science · Physics 2015-05-20 Muhammad Usman , Susannah Heck , Edmund Clarke , Peter Spencer , Hoon Ryu , Ray Murray , Gerhard Klimeck

We have studied theoretically the type-II GaAsSb capped InAs quantum dots for two structures differing in the composition of the capping layer, being either (i) constant or (ii) with Sb accumulation above the apex of the dot. We have found…

Mesoscale and Nanoscale Physics · Physics 2023-07-19 P. Klenovsky , V. Krapek , J. Humlicek

We present an atomistic study of the strain field, the one-particle electronic spectrum and the oscillator strength of the fundamental optical transition in chemically disordered In$_{x}$Ga$_{1-x}$As pyramidal quantum dots (QDs).…

Materials Science · Physics 2007-05-23 R. Santoprete , P. Kratzer , M. Scheffler , R. B. Capaz , Belita Koiller

This work presents an analysis of the electronic and optical properties of InAs/GaAs columnar quantum dots (QDs) by performing multi-million-atom tight-binding simulations. The plots of the polarisation-dependent ground state optical…

Mesoscale and Nanoscale Physics · Physics 2020-06-30 Muhammad Usman

A systematic manipulation of the morphology and the optical emission properties of MOVPE grown ensembles of InAs/InP quantum dots is demonstrated by changing the growth kinetics parameters. Under non-equilibrium conditions of a…

Materials Science · Physics 2007-05-23 Bhavtosh Bansal , M. R. Gokhale , Arnab Bhattacharya , B. M. Arora

Polarization-resolved single dot spectroscopy performed on (211)B InAs/GaAs quantum dots reveals that the fine structure splitting of the excitonic levels in these dots is much lower compared to the usual (100)-grown InAs dots.…

We perform spatial point analysis of InAs quantum dot nucleation sites and surface reconstruction domain pattern on an InAs wetting layer, giving insights for quantum dot nucleation mechanism. An InAs wetting layer grown to 1.5 monolayers…

Materials Science · Physics 2015-05-19 Tomoya Konishi , Shiro Tsukamoto

A study of previously overlooked structural and optical properties of InGaAs heterostructures grown on (111)B oriented GaAs substrates patterned with inverted 7.5 um pitch pyramidal recesses is presented. First, the composition of the…

We study the polarization response of the emission from type-II GaAsSb capped InAs quantum dots. The theoretical prediction based on the calculations of the overlap integrals of the single-particle states obtained in the k.p framework is…

Mesoscale and Nanoscale Physics · Physics 2016-12-13 P. Klenovsky , D. Hemzal , P. Steindl , M. Zikova , V. Krapek , J. Humlicek

Most self-assembled quantum dot molecules are intrinsically asymmetric with inequivalent dots resulting from imperfect control of crystal growth. We have grown vertically-aligned pairs of InAs/GaAs quantum dots by molecular beam epitaxy,…

Molecular states in a SINGLE PAIR of strongly coupled self-assembled InAs quantum dots are investigated using a sub-micron sized single electron transistor containing just a few pairs of coupled InAs dots embedded in a GaAs matrix. We…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 T. Ota , M. Stopa , M. Rontani , T. Hatano , K. Yamada , S. Tarucha , H. Z. Song , Y. Nakata , T. Miyazawa , T. Ohshima , N. Yokoyama

We study the electronic and optical properties of laterally coupled InGaAs/GaAs quantum dot molecules under lateral electric field. We find that electrons perceive the double-dot structure as a compound single object, while the holes…

The two- to three-dimensional growth transition in the InAs/GaAs(001) heterostructure has been investigated by atomic force microscopy. The kinetics of the density of three dimensional quantum dots evidences two transition thresholds at…

Materials Science · Physics 2009-11-11 F. Arciprete , E. Placidi , V. Sessi , M. Fanfoni , F. Patella , A. Balzarotti
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