Abstract

Taking into account anisotropy, nonparabolicity of the conduction band, and geometrical confinement, we discuss the heavy-hole excitonic states in a strained GaxIn1-xAs/GaAs quantum dot for various Ga alloy contents. The strained quantum dot is considered as a spherical InAs dot surrounded by a GaAs barrier material. The dependence of the effective excitonic g-factor as a function of dot radius and Ga ion content is numerically measured. Interband optical energy with and without the parabolic effect is computed using structural confinement. The interband matrix element for different Ga concentrations is also calculated. The oscillator strength of interband transitions on the dot radius is studied at different Ga concentrations in the GaxIn1-xAs/GaAs quantum dot. Heavy-hole excitonic absorption spectra are recorded for various Ga alloy contents in the GaxIn1-xAs/GaAs quantum dot. Results show that oscillator strength diminishes when dot size decreases because of the dominance of the quantum size effect. Furthermore, exchange enhancement and exchange splitting increase as exciton confinement increases.

© 2013 Chinese Optics Letters

Strain effects on exciton saturation in quantum-well optical modulator devices

Adriaan J. Sengers, Leung Tsang, and Shun-Lien Chuang
J. Opt. Soc. Am. B 13(12) 2750-2758 (1996)

Exciton dynamics and spin relaxation in unstrained and tensile-strained quantum wells

L. Muñoz, E. Pérez, V. Bellani, S. Zimmermann, L. Viña, K. Ploog, E. S. Koteles, and K. M. Lau
J. Opt. Soc. Am. B 13(5) 994-999 (1996)

Electronic structure and optical properties of PbS and PbSe quantum dots

Inuk Kang and Frank W. Wise
J. Opt. Soc. Am. B 14(7) 1632-1646 (1997)

Oscillatory acoustic phonon relaxation of excitons in quantum dot molecules

Juan E. Rolon, Kushal C. Wijesundara, Sergio E. Ulloa, Allan S. Bracker, Daniel Gammon, and Eric A. Stinaff
J. Opt. Soc. Am. B 29(2) A146-A153 (2012)

Room-temperature excitonic nonlinear-optical effects in semiconductor quantum-well structures

D. S. Chemla and D. A. B. Miller
J. Opt. Soc. Am. B 2(7) 1155-1173 (1985)