Variational tight-binding theory of excitons in compositionally modified semiconductor superlattices
Author
Luban, Marshall
Reynolds, Joseph P.
Luscombe, James H.
Date
1999Metadata
Show full item recordAbstract
We present results for the binding energy of an exciton formed when an electron–hole
pair is photoexcited within a single, compositionally modified layer of a semiconductor
superlattice, for example by adding a small percentage of In atoms to a single GaAs layer
of a GaAs/AlGaAs system. Such a system could serve as the basis for spatially-selective
photoexcitation, a process whereby a laser pulse would create electron–heavy-hole pairs
exclusively in the modified layer.We first derive an effective one-dimensional (1D) Hamiltonian
for an electron, by averaging the 3D electron–hole Hamiltonian using a one-parameter
trial wavefunction, which is dependent on the in-plane relative coordinates, as well as a
normalized Wannier orbital for a single hole. The exciton binding energy is then obtained
by computing the lowest bound-state energy of the effective 1D electron Hamiltonian in
the nearest-neighbor tight-binding approximation. As a demonstration of the effectiveness
of our approach, we find that for periodic superlattices our results for the exciton binding
energy are in very good agreement both with experiment and the results of other theoretical
calculations.
Description
Article No. spmi.1998.0599
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.Collections
Related items
Showing items related by title, author, creator and subject.
-
Classical trajectory calculations of the energy distribution of ejected atoms from ion bombarded single crystals
Garrison, B.J.; Winograd, N.; Harrison, D.E., Jr. (Elsevier, 1979-02-28);The energy distribution of particles ejected from single crystal surfaces has been calculated using classical dynamics. The model utilizes a microcrystallite of 4 layers with ~60 atoms/layer which is bombarded by 600 eV ... -
Simulations of the TJNAF free electron laser with a negative taper and laser damage studies
Christodoulou, Adamantios (Monterey, California. Naval Postgraduate School, 2000-12);The Free Electron Laser (FEL) is a candidate for a future close-in weapon system that will provide a longer protective range for missile destruction. The FEL is also tunable to wavelengths that would give good atmospheric ... -
Metalloid aluminum clusters with fluorine
Lentsoane, Nape D. (Monterey, California: Naval Postgraduate School, 2016-12);Metals have a very high energy density compared to explosives, but typically release this energy slowly via diffusion-limited combustion. There is recent interest in using molecular-scale metalloid clusters as a way to ...