Development and assessment of coupled wave theory of axial propagation in thin-film helicoidal bi-anisotropic media. Part 2: Dichroisms, ellipticity transformation and optical rotation

The coupled wave theory (CWT) for axial propagation of light in dielectric thin-film helicoidal bi-anisotropic mediums is exploited to obtain simple e xpressions for true and apparent circular dichroisms, true and apparent lin ear dichroisms, transmission ellipticity, and optical rotation. The effect of weak isotropic absorption on the circular Bragg phenomenon is elucidated , in terms of simple expressions. Comparison is made with exact results obt ained with the full electromagnetic analysis (FEMA), any differences betwee n the CWT and the FEMA results being due to the neglect of cross-polarized scattering by the CWT.