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

Article

关键词: BAND-STRUCTURE;    DISPERSION;    DYNAMICS;    SUPERLATTICES;    LOCALIZATION;    RELAXATION;    ABSORPTION;    ENERGY;    MODEL;   

DOI  :  10.1103/PhysRevB.61.10854

来源: SCIE

【 摘 要 】

We present high-quality numerical calculations of the exciton center-of-mass 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- and light-hole bands is taken fully into account. An optimized center-of-mass transformation enhances numerical convergence. We derive an easy-to-use semianalytical expression for the exciton ground-state mass from an ansatz for 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 multiband calculations of the exciton ground-state dispersion using a finite-difference scheme in real space, which can be applied to rather general heterostructures.

【 授权许可】

Free