Investigation of the dependence of volume, cap layer, and aspect ratio on the strain distribution and electronic structure of self-organized InAs/GaAs quantum dot

On the basis of the finite element approach, we systematically investigated the strain field distribution of conical-shaped InAs/GaAs self-organized quantum dot using the two-dimensional axis-symmetric model. The normal strain, the hydrostatic strain and the biaxial strain components along the center axis path of the quantum dots are analyzed. The dependence of these strain components on volume, height-over-base ratio and cap layer (covered by cap layer or uncovered quantum dot) is investigated for the quantum grown on the (001) substrate. The dependence of the carriers' confining potentials on the three circumstances discussed above is also calculated in the framework of eight-band k·p theory. The numerical results are in good agreement with the experimental data of published literature.

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Influence of Strain-Reducing Layer on Strain Distribution of Self-Organized InAs/GaAs Quantum Dot and Redshift of Photoluminescence Wavelength

Chinese Physics Letters ◽

10.1088/0256-307x/25/5/089 ◽

2008 ◽

Vol 25 (5) ◽

pp. 1850-1853 ◽

Cited By ~ 17

Author(s):

Liu Yu-Min ◽

Yu Zhong-Yuan ◽

Ren Xiao-Min

Keyword(s):

Quantum Dot ◽

Strain Distribution ◽

Self Organized ◽

Gaas Quantum Dot

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STRAIN DISTRIBUTION AND ELECTRONIC STRUCTURE OF SELF-ORGANIZED InAs/GaAs QUANTUM DOTS

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863509004816 ◽

2009 ◽

Vol 18 (04) ◽

pp. 553-560

Author(s):

YUMIN LIU ◽

ZIHUAN XU ◽

ZHONGYUAN YU ◽

BOYONG JIA ◽

WENJUAN LU ◽

...

Keyword(s):

Quantum Dots ◽

Electronic Structure ◽

Quantum Dot ◽

Strain Distribution ◽

Energy Levels ◽

Electronic Energy ◽

Conduction Band Edge ◽

Three Dimension ◽

Self Organized ◽

Piezoelectric Effects

This paper presents a finite element method for calculating the strain distribution, piezoelectric effects and their influences on the electronic structure of self-organized InAs/GaAs quantum dots. The models used for strain calculations are based on the continuum elastic theory, which is capable of treating the quantum dot of arbitrary shapes. A truncated pyramid shaped quantum dot model including the wetting layer is adopted in this work. The electronic energy levels of the InAs/GaAs systems are calculated by solving the three-dimension effective mass Schrödinger equation including the influences on the modification of conduction band edge due to the strain and piezoelectricity. The calculated results indicate that both strain and piezoelectric effects should be considered, especially in treating the electronic structure and optical characteristics for device applications.

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Geometry and material parameter dependence of InAs/GaAs quantum dot electronic structure

Physical Review B ◽

10.1103/physrevb.60.2869 ◽

1999 ◽

Vol 60 (4) ◽

pp. 2869-2874 ◽

Cited By ~ 85

Author(s):

Craig Pryor

Keyword(s):

Electronic Structure ◽

Quantum Dot ◽

Material Parameter ◽

Parameter Dependence ◽

Gaas Quantum Dot

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Analytic Calculation About the Strain Distribution of Any-Shaped Self-Organized Quantum Dot

First International Conference on Integration and Commercialization of Micro and Nanosystems, Parts A and B ◽

10.1115/mnc2007-21371 ◽

2007 ◽

Author(s):

Yumin Liu ◽

Zhongyuan Yu

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Quantum Dot ◽

Function Approximation ◽

Strain Distribution ◽

Function Technique ◽

Plane Wave Expansion ◽

The Finite Element Method ◽

Self Organized ◽

Element Method

The strain distribution of quantum dots is analytically calculated using the Green’s function technique; the general expressions for any shaped quantum dot are derived. As examples, this method is applied to cube, pyramid column, and taper-shaped quantum dot. Our expressions are correct comparing with the calculated results by finite element method and finite difference. This approach is very powerful and can be applied to any-shaped quantum dot, especially this method can directly used in the calculation of electronic structure of quantum dot by the envelop function approximation or plane wave expansion methods, because the analytic expression can exactly calculate the strain at any position. In the paper, we give the strain distribution of four types of shaped quantum dot, and some comparisons are given with the results calculated by the finite element method.

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