Electron-related optical properties in T-shaped AlxGa1−xAs/GaAs quantum wires and dots

ABSTRACT: The electronic structure and the intersubband optical absorption and relative refractive index change coefficients in T-shaped two-dimensional quantum dot and one-dimensional quantum wire are studied. The T-shaped quantum dot is embedded in AlxGa1−xAs, with x = 0.35, the arm region has x =...

Full description

Autores:
Mora Ramos, Miguel Eduardo
Duque Echeverri, Carlos Alberto
Martínez Orozco, Juan Carlos
Tipo de recurso:
Article of investigation
Fecha de publicación:
2015
Institución:
Universidad de Antioquia
Repositorio:
Repositorio UdeA
Idioma:
eng
OAI Identifier:
oai:bibliotecadigital.udea.edu.co:10495/31006
Acceso en línea:
https://hdl.handle.net/10495/31006
Palabra clave:
Electrones
Electrons
Análisis espectral
Spectrum analysis
Óptica
Optics
Quantum dots
Rights
openAccess
License
http://creativecommons.org/licenses/by/2.5/co/
Description
Summary:ABSTRACT: The electronic structure and the intersubband optical absorption and relative refractive index change coefficients in T-shaped two-dimensional quantum dot and one-dimensional quantum wire are studied. The T-shaped quantum dot is embedded in AlxGa1−xAs, with x = 0.35, the arm region has x = 0 whereas different values of the Al molar fraction are present for the T-stem region (x = 0, 0.7, 0.14, and 0.21). The model calculation is useful for studying both a 1D quantum wire of T-shaped cross- section and a 2D T-shaped quantum dot. The conduction and valence band states are described within the effective mass and parabolic band approximations. The agreement between calculated photoluminescence peak energy transitions and previously reported experimental values in such T-shaped quantum well wires is discussed. The electron-related optical coefficients are calculated using a density-matrix expansion with the inclusion of the linear and third-order nonlinear contributions to the dielectric susceptibility. The results for this optical response are presented as functions of the Al molar fraction, as well as of the polarization, and intensity of the incident light.