Moments-based tight-binding calculations of local electronic structure in InAs/GaAs quantum dots for comparison to experimental measurements

Jun Qiang Lu, H. T. Johnson, V. D. Dasika, R. S. Goldman

Research output: Contribution to journalArticle

Abstract

Local electronic properties of InAsGaAs nanostructures are studied using a real-space moments method s p3 d5 s* tight-binding approach. The order (N) method is unique because it allows for accurate and highly resolved determination of local density of states that accounts for local strain, disorder, and defects, without diagonalization of the full tight-binding Hamiltonian. The effects of free surfaces and strain are first investigated by considering pure, cuboidal GaAs nanostructures. The quantum confinement in an embedded InAs quantum dot is then shown directly through the local densities of states projected on different atoms in the structure. The relationship between effective energy band gap and quantum dot size is mapped onto a simple equation. Finally, the real-space study is applied to quantum dot structures observed experimentally using scanning tunneling microscopy. Atomic positions are obtained from the images and used as input into the tight-binding calculations in order to study interfacial effects on the local electronic structure of real embedded quantum dots.

Original languageEnglish (US)
Article number053109
Pages (from-to)1-3
Number of pages3
JournalApplied Physics Letters
Volume88
Issue number5
DOIs
StatePublished - Feb 10 2006

Fingerprint

quantum dots
electronic structure
moments
energy bands
scanning tunneling microscopy
disorders
defects
electronics
atoms

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Moments-based tight-binding calculations of local electronic structure in InAs/GaAs quantum dots for comparison to experimental measurements. / Lu, Jun Qiang; Johnson, H. T.; Dasika, V. D.; Goldman, R. S.

In: Applied Physics Letters, Vol. 88, No. 5, 053109, 10.02.2006, p. 1-3.

Research output: Contribution to journalArticle

@article{14b9447bdcba43bb8d23faed6fe06e15,
title = "Moments-based tight-binding calculations of local electronic structure in InAs/GaAs quantum dots for comparison to experimental measurements",
abstract = "Local electronic properties of InAsGaAs nanostructures are studied using a real-space moments method s p3 d5 s* tight-binding approach. The order (N) method is unique because it allows for accurate and highly resolved determination of local density of states that accounts for local strain, disorder, and defects, without diagonalization of the full tight-binding Hamiltonian. The effects of free surfaces and strain are first investigated by considering pure, cuboidal GaAs nanostructures. The quantum confinement in an embedded InAs quantum dot is then shown directly through the local densities of states projected on different atoms in the structure. The relationship between effective energy band gap and quantum dot size is mapped onto a simple equation. Finally, the real-space study is applied to quantum dot structures observed experimentally using scanning tunneling microscopy. Atomic positions are obtained from the images and used as input into the tight-binding calculations in order to study interfacial effects on the local electronic structure of real embedded quantum dots.",
author = "Lu, {Jun Qiang} and Johnson, {H. T.} and Dasika, {V. D.} and Goldman, {R. S.}",
year = "2006",
month = "2",
day = "10",
doi = "10.1063/1.2171473",
language = "English (US)",
volume = "88",
pages = "1--3",
journal = "Applied Physics Letters",
issn = "0003-6951",
publisher = "American Institute of Physics Publising LLC",
number = "5",

}

TY - JOUR

T1 - Moments-based tight-binding calculations of local electronic structure in InAs/GaAs quantum dots for comparison to experimental measurements

AU - Lu, Jun Qiang

AU - Johnson, H. T.

AU - Dasika, V. D.

AU - Goldman, R. S.

PY - 2006/2/10

Y1 - 2006/2/10

N2 - Local electronic properties of InAsGaAs nanostructures are studied using a real-space moments method s p3 d5 s* tight-binding approach. The order (N) method is unique because it allows for accurate and highly resolved determination of local density of states that accounts for local strain, disorder, and defects, without diagonalization of the full tight-binding Hamiltonian. The effects of free surfaces and strain are first investigated by considering pure, cuboidal GaAs nanostructures. The quantum confinement in an embedded InAs quantum dot is then shown directly through the local densities of states projected on different atoms in the structure. The relationship between effective energy band gap and quantum dot size is mapped onto a simple equation. Finally, the real-space study is applied to quantum dot structures observed experimentally using scanning tunneling microscopy. Atomic positions are obtained from the images and used as input into the tight-binding calculations in order to study interfacial effects on the local electronic structure of real embedded quantum dots.

AB - Local electronic properties of InAsGaAs nanostructures are studied using a real-space moments method s p3 d5 s* tight-binding approach. The order (N) method is unique because it allows for accurate and highly resolved determination of local density of states that accounts for local strain, disorder, and defects, without diagonalization of the full tight-binding Hamiltonian. The effects of free surfaces and strain are first investigated by considering pure, cuboidal GaAs nanostructures. The quantum confinement in an embedded InAs quantum dot is then shown directly through the local densities of states projected on different atoms in the structure. The relationship between effective energy band gap and quantum dot size is mapped onto a simple equation. Finally, the real-space study is applied to quantum dot structures observed experimentally using scanning tunneling microscopy. Atomic positions are obtained from the images and used as input into the tight-binding calculations in order to study interfacial effects on the local electronic structure of real embedded quantum dots.

UR - http://www.scopus.com/inward/record.url?scp=31944446256&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=31944446256&partnerID=8YFLogxK

U2 - 10.1063/1.2171473

DO - 10.1063/1.2171473

M3 - Article

AN - SCOPUS:31944446256

VL - 88

SP - 1

EP - 3

JO - Applied Physics Letters

JF - Applied Physics Letters

SN - 0003-6951

IS - 5

M1 - 053109

ER -