Size and piezoelectric effects on optical properties of self-assembled ingaas/gaas quantum dots
Journal
American Society of Mechanical Engineers, Materials Division (Publication) MD
ISBN (of the container)
9780791837900
ISBN
9780791837900
0791837904
Date Issued
2006-01-01
Author(s)
Abstract
Size effects on optical properties of self-assembled quantum dots are analyzed based on the theories of linear elasticity and of strain-dependent k-p with the aid of finite element analysis. The quantum dot is made of InGaAs with truncated pyramidal shape on GaAs substrate. The three-dimensional steady-state effective-mass Schrödinger equation is adopted to find confined energy levels as well as wave functions both for electrons and holes of the quantum-dot nanostructures. Strain-induced as well as piezoelectric effects are taken into account in the carrier confinement potential of Schrödinger equation. The optical transition energies of quantum dots, computed from confined energy levels for electrons and holes, are significantly different for several quantum dots with distinct sizes. It is found that for QDs with the the larger the volume of QD is, the smaller the values of the optical transition energy. Piezoelectric effect, on the other hand, splits the p-like degeneracy for the electron first excited state about 1-7 meV, and leads to anisotropy on the wave function.
Event(s)
2006 ASME International Mechanical Engineering Congress and Exposition, IMECE 2006, 5 November 2006 through 10 November 2006, Code 69689
Subjects
Finite element method
Induced strain
Optical property
Piezoelectric effect
Quantum dot
Type
conference paper