The pseudo-Brewster angle ϕpB of minimum reflectance for p-polarized light and the principal angle ϕ¯ at which incident linearly polarized light of the proper azimuth is reflected circularly polarized are considered as functions of the complex relative dielectric function ε of a dielectric–conductor interface over the entire complex ε plane. In particular, the spread of ϕ¯for a given ϕpB is determined, and the maximum difference (ϕ¯−ϕpB)max is obtained as a function of ϕpB . The maximum difference (ϕ¯−ϕpB)max approaches 45° and 0 in the limit as ϕpB→0 and 90°, respectively. ForϕpB<22.666° , multiple principal angles ϕ¯i , i=1,2,3 , appear for each ε in a subdomain of fractional optical constants. This leads to an elaborate pattern of multiple solution branches for the difference ϕ¯i−ϕpB , i=1,2,3 , as is illustrated by several examples.
Journal of the Optical Society of America A
R. M. A. Azzam and A. Alsamman, "Plurality of principal angles for a given pseudo-Brewster angle when polarized light is reflected at a dielectric-conductor interface," J. Opt. Soc. Am. A 25, 2858-2864 (2008)