Modulation Spectroscopy

Abstract

The interaction between light and atoms or molecules in the solid state can be described by a complex refractive index or dielectric constant tensor ϵ. The dependence of ϵ on the wavelength of the incident radiation yields information about the energy bands of the electrons in the solid, and this dependence can be obtained by measuring the variation of reflectivity or transmission of a sample as a function of wavelength and polarization.