title: Maximum reflectance difference for incident p- and s-polarized light at air-dielectric interfaces.
abstract: New features related to the reflection of p- and s-polarized light at optically isotropic air-dielectric interfaces are determined. The intensity reflectance difference, RD = Rs - Rp, is maximum at an angle of incidence (AOI) ϕ = ϕMD in the range between the Brewster angle and grazing incidence. Both ϕMD and (Rs - Rp)max are calculated as functions of substrate refractive index n. Explicit expressions are obtained for the two angles of incidence, one below and one above the Brewster angle, at which the condition Rs = 2Rp is satisfied. Measurement of such angles enables the determination of n of transparent materials using a simple null-seeking spectroscopic ellipsometer with a ϕ-2ϕ goniometer. Finally, the AOI at which Rp'' = 0 (point of inflection in the Rp-versus-ϕ curve) is identified, and the equation that determines such an angle is also derived analytically.
authors.forename: R M A
authors.initials: RM
authors.lastname: Azzam