Optical properties of materials

Starting from Maxwell equations and constitutive equations of a medium we consider the linear macroscopic optical response for homogeneous, isotropic, non-magnetic materials. The complex dielectric function and complex refractive index are derived with their connections with optical reflectance, transmittance and absorptance, for both unpolarized and polarized light. A few selected examples of optical response for solids (metals, semiconductors and insulators) are presented, together with the simplest classical and quantum models producing analytical expressions for the optical structures observed in experimental spectra. Analytical models give insights into optical response of materials and heterostructures, and should be used both to fit experimental data and simulate performances of electronic and photonic devices.