Electronic and optical properties of InGaAs/GaAs quantum dots with tunable aspect-ratio
Artikel i vetenskaplig tidskrift, 2014

In this paper, a combined approach of finite element method (FEM) and quadratic programming optimization method is proposed to investigate the nonuniform equilibrium composition profile of InGaAs/GaAs quantum dots (QDs) in the framework of Gibbs energy optimization (GEO). The proposed QDs are varied with aspect ratio from 0.3 to 0.5. The wave functions of electron and heavy hole are predicted by using the k . p method. The changes of wave functions before and after optimization can be observed by using composition optimization. Both the eigenvalues and transition energy change obviously with the increasing aspect ratio. The linear optical absorption coefficients corresponding to the interband ground state transition are obtained via the density matrix approach and perturbation expansion method. The numerical results reveal that the aspect ratio and composition profile play significant roles in determining the electronic and optical properties.

finite element method

SURFACE

electronic and optical structure

InGaAs/GaAs QDs

nonuniform composition

GROWTH

NANOCRYSTALS

MICROSCOPY

Författare

P. F. Lu

Beijing University of Posts and Telecommunications (BUPT)

X. X. Zhong

Beijing University of Posts and Telecommunications (BUPT)

C. Sun

Beijing University of Posts and Telecommunications (BUPT)

Z. Y. Yu

Beijing University of Posts and Telecommunications (BUPT)

L. H. Han

Beijing University of Posts and Telecommunications (BUPT)

Shu Min Wang

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Modern Physics Letters B

0217-9849 (ISSN)

Vol. 28 9

Ämneskategorier

Den kondenserade materiens fysik

DOI

10.1142/s0217984914500729