Polarization-dependent quantum beats of four-wave mixing in the Luttinger model for bulk semiconductors

Abstract

We examine the description of quantum beats in four-wave mixing with bulk semiconductors within the framework of the Luttinger-Kohn model. An analytic expression for their dependence on the relative linear polarization of pump and probe is derived, taking only the band structure and coherent interaction of the light waves with the semiconductor medium into account. Herewith all features seen in experiments are very well reproduced, e.g., the vanishing of the beats for an angle 0 Ϸ 76°between the polarizations of pump and probe. Therefore, as opposed to general belief based on earlier theoretical work, no ad hoc exciton-exciton Coulomb interaction has to be invoked to describe the observed phase and magnitude of the quantum beats for copolarized or for cross-polarized test and pump pulses.