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 expressions for true and apparent circular dichroisms, true and apparent linear 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 obtained with the full electromagnetic analysis (FEMA), any differences between the CWT and the FEMA results being due to the neglect of cross-polarized scattering by the CWT.