Determination of the far-infrared dielectric function of a thin InGaAs layer using a detuned Salisbury screen

Abstract

We present a method to determine the far-infrared dielectric function parameters of a thin In0.53Ga0.47As layer. We use a detuned Salisbury screen configuration to enhance the interaction of far infrared light with optical phonons in the InGaAs layer. From polarized angle-resolved reflectance spectrum and Raman spectroscopy, we obtain experimental data that we adjust using a dielectric function model fulfilling causality. We provide a complete set of parameters for an analytic expression of In0.53Ga0.47As dielectric function in the optical phonon frequency range and deduce a value for the static dielectric constant.