Physical review. B, Condensed matter

Theory of coherent propagation of a light wave in semiconductors. II

Zizhao Gan, Guozhen Yang

Published Dec 15, 1982• 5 citations

Abstract

This paper contains the second part of a theory of the coherent propagation of a light wave in semiconductors. After considering the interaction among the electrons, we discuss the matter of the interaction of a semiconductor with light and derive equations of motion for the polarization wave of the excitons which have been excited by the light. We show how our equations can be approximated by linear ones and how the exciton polarization wave can be regarded as a Bose field in the limit of low excitation. In this paper we also discuss in detail the problem of the coherent excitation of discrete exciton levels. We show that the coherently excited discrete exciton is approximately equivalent to a two-level atom which is excited by a light wave; the atom energy-level spacing is a function of the degree of excitation, and the density of equivalent "two-level atoms" is determined by features of the exciton-state wave function.

DOI: 10.1103/physrevb.26.6833

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