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Related papers: Electronic structure of strained InP/GaInP quantum…

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In this work we present a comparison of multiband k.p-models, the effective bond-orbital approach, and an empirical tight-binding model to calculate the electronic structure for the example of a truncated pyramidal GaN/AlN self-assembled…

Materials Science · Physics 2009-11-13 Oliver Marquardt , Daniel Mourad , Stefan Schulz , Tilmann Hickel , Gerd Czycholl , Jörg Neugebauer

We propose a new system where electron and hole states are electrostatically confined into a quantum ring in bilayer graphene. These structures can be created by tuning the gap of the graphene bilayer using nanostructured gates or by…

Mesoscale and Nanoscale Physics · Physics 2015-05-14 M. Zarenia , J. M. Pereira , F. M. Peeters , G. A. Farias

We present an analytically solvable model of $P$ colinear, two-dimensional quantum dots, each containing two electrons. Inter-dot coupling via the electron-electron interaction gives rise to sets of entangled ground states. These ground…

Condensed Matter · Physics 2009-10-28 Simon C. Benjamin , Neil F. Johnson

The effect of wetting layers on the strain and electronic structure of InAs self-assembled quantum dots grown on GaAs is investigated with an atomistic valence-force-field model and an empirical tight-binding model. By comparing a dot with…

Materials Science · Physics 2009-11-10 Seungwon Lee , Olga L. Lazarenkova , Fabiano Oyafuso , Paul von Allmen , Gerhard Klimeck

We present a systematic study of the influence of elastic strain relaxation on the built-in electrostatic potentials and the electronic properties of axial (In,Ga)N/GaN nanowire heterostructures. We employ and evaluate analytical and…

Mesoscale and Nanoscale Physics · Physics 2017-05-24 Oliver Marquardt , Thilo Krause , Vladimir Kaganer , Javier Martin-Sanchez , Michael Hanke , Oliver Brandt

Detailed theoretical studies of the electronic structure of (InGa)(AsSb)/GaAs/GaP quantum dots are presented. This system is unique since it exhibits concurrently direct and indirect transitions both in real and momentum space and is…

Mesoscale and Nanoscale Physics · Physics 2019-09-18 Petr Klenovský , Andrei Schliwa , Dieter Bimberg

Electron orbits are calculated in solitary two-dimensional axisymmetric electrostatic potential structures, typical of plasma electron holes, in order to establish the conditions for the particles to remain trapped. Analytic calculations of…

Space Physics · Physics 2020-08-10 I H Hutchinson

Coupled electron-hole states are realized in a system consisting of a combination of an electrostatic potential barrier and ring-shaped potential well, which resembles a circular dipole. A perpendicular magnetic field induces confined…

Mesoscale and Nanoscale Physics · Physics 2019-04-05 R. Van Pottelberge , F. M. Peeters

We present atomistic computations within an empirical pseudopotential framework for the electron $s$-shell ground state $g$ tensor of InGaAs quantum dots (QDs) embedded to host matrices that grant electronic confinement. A large structural…

Mesoscale and Nanoscale Physics · Physics 2021-04-13 Mustafa Kahraman , Ceyhun Bulutay

We present a theoretical study of the electronic structures of freestanding nanowires made from gallium phosphide (GaP)--a III-V semiconductor with an indirect bulk bandgap. We consider [001]-oriented GaP nanowires with square and…

Mesoscale and Nanoscale Physics · Physics 2016-06-21 Gaohua Liao , Ning Luo , Ke-Qiu Chen , H. Q. Xu

Atomistic electronic structure calculations are performed to study the coherent inter-dot couplings of the electronic states in a single InGaAs quantum dot molecule. The experimentally observed excitonic spectrum [12] is quantitatively…

Mesoscale and Nanoscale Physics · Physics 2013-08-01 Muhammad Usman , Yui-Hong Matthias Tan , Hoon Ryu , Shaikh S. Ahmed , Hubert Krenner , Timothy B. Boykin , Gerhard Klimeck

While electronic and spectroscopic properties of self-assembled In_{1-x}Ga_{x}As/GaAs dots depend on their shape, height and alloy compositions, these characteristics are often not known accurately from experiment. This creates a difficulty…

Materials Science · Physics 2009-11-11 Gustavo A. Narvaez , Gabriel Bester , Alex Zunger

The ground state structure of few-electron concentric double quantum rings is investigated within the local spin density approximation. Signatures of inter-ring coupling in the addition energy spectrum are identified and discussed. We show…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 J. I. Climente , J. Planelles , M. Barranco , F. Malet , M. Pi

Spin manipulation in coupled quantum dots is of interest for quantum information applications. Control of the exchange interaction between electrons and holes via an applied electric field may provide a promising technique for such spin…

We demonstrate an efficient method to engineer the quantum confinement in a system of two quantum dots grown in a vertical stack. We achieve this by using materials with a different lattice constant for the growth of the outer and inner…

Mesoscale and Nanoscale Physics · Physics 2015-02-13 Ł. Kłopotowski , P. Wojnar , S. Kret , M. Parlińska-Wojtan , K. Fronc , G. Karczewski , T. Wojtowicz

We electrically measure intrinsic silicon quantum dots with electrostatically defined tunnel barriers. The presence of both p-type and n-type ohmic contacts enables the accumulation of either electrons or holes. Thus we are able to study…

Mesoscale and Nanoscale Physics · Physics 2015-06-23 A. C. Betz , M. F. Gonzalez-Zalba , G. Podd , A. J. Ferguson

We report experiments on a quantum electron interferometer fabricated from high mobility, low density GaAs/AlGaAs heterostructure material. In this device, a nearly circular electron island is defined by four front gates deposited in etched…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 F. E. Camino , W. Zhou , V. J. Goldman

A multiscale approach was adopted for the calculation of confined states in self-assembled semiconductor quantum dots (QDs). While results close to experimental data have been obtained with a combination of atomistic strain and…

Mesoscale and Nanoscale Physics · Physics 2014-09-16 Parijat Sengupta , Sunhee Lee , Sebastian Steiger , Hoon Ryu , Gerhard Klimeck

The electronic properties of the twisted InSe bilayer are studied by large-scale density functional theory. Spectral Function Unfolding reveals that the electronic structure of the twisted system can be described in terms of a combination…

Materials Science · Physics 2022-02-28 Siow Mean Loh , Nicholas D. M. Hine

In this paper, we address the problem of luminescence polarization in the case of nanostructures characterized by an in-plane shape asymmetry. We develop a simple semi-qualitative model revealing the mechanism that accounts for the…

Mesoscale and Nanoscale Physics · Physics 2012-01-20 Piotr Kaczmarkiewicz , Anna Musiał , Grzegorz Sęk , Paweł Podemski , Paweł Machnikowski , Jan Misiewicz