Center-of-mass properties of the exciton in quantum wells

Citation
A. Siarkos et al., Center-of-mass properties of the exciton in quantum wells, PHYS REV B, 61(16), 2000, pp. 10854-10867
Citations number
43
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
10980121 → ACNP
Volume
61
Issue
16
Year of publication
2000
Pages
10854 - 10867
Database
ISI
SICI code
1098-0121(20000415)61:16<10854:CPOTEI>2.0.ZU;2-M
Abstract
We present high-quality numerical calculations of the exciton center-of-mas s dispersion for GaAs/AlxGa1-xAs quantum wells of widths in the range 2-20 nm. The (k) over right arrow.(p) over right arrow coupling of the heavy- an d light-hole bands is taken fully into account. An optimized center-of-mass transformation enhances numerical convergence. We derive an easy-to-use se mianalytical expression for the exciton ground-state mass from an ansatz fo r the exciton wave function at a finite momentum. It is checked against the numerical results and found to give very good results. We also show multib and calculations of the exciton ground-state dispersion using a finite-diff erence scheme in real space, which can be applied to rather general heteros tructures.