Reflectance of an absorbing medium for incident light of arbitrary polarization: correlation between the oscillatory behavior and the complex ∊ plane

The reflectance of an absorbing medium R(theta)(ø) for incident light of an arbitrary state of polarization is considered as a function of the compex dielectic constant epsilon; ø is the angle incidence and theta is an incident polarization parameter, for which cos(2)theta and sin(2)theta give the power fractions of incident radiation that are p- and s-polarized, respectively. Our objective is to explore the complex epsilon-plane and define the domains for which the different types of R(theta)(ø) vs ø curves (monotonic, single minimum, and secondary maximum and minimum) occur. An ethanolic solution of Rhodamine B, an organic laser dye luminofor with a well-defined resonance absorption spectrum, was chosen as the absorbing medium. We were able to define the criteria for three distinctly different types of behavior of R(theta)(ø).