Theory of electroabsorption by anisotropic and layered semiconductors. I. Two-dimensional excitons in a uniform electric field

Abstract

A basis for the theory of electroabsorption by excitons in anisotropic and layered semiconductors is developed, in which the excitons are assumed to be two dimensional. The effective-mass equation for a two-dimensional exciton in a uniform electric field of arbitrary strength is solved exactly (numerically), and the electroabsorption spectra computed for direct allowed, direct "forbidden" (second class), and indirect allowed transitions. The calculated spectra are compared with corresponding spectra for three-dimensional excitons and with spectra calculated neglecting the electron-hole interaction. The results are tabulated in a form that facilitates comparison with experimental data.