Estimation of Conduction as Well as Donor Electron Density Through Far-Infrared Resonant Faraday Effect

Abstract

We have investigated resonant Faraday effect (RFE), so-called nonlinear Faraday effect, caused by conduction and donor electrons in n-InSb and n-GaAs. Experiments were carried out with using the magneto-optical spectroscopic system combined with two linear polarizers put in before and behind a sample. The rotation angle and the ellipticity for the far-infrared light with elliptical polarization transmitted through the sample were analyzed on the basis of spectra obtained under different experimental configuration for angles between the axes of the polarizer and the analyzer. We have observed some characteristic features associated with RFE in spectra of two samples. Tapping into these features, we could successfully determine the relaxation times and the densities of conduction and donor electrons in the semiconductors.