Stokes–Mueller formalism of spectrally-resolved transmitted light in an artificial opal

Abstract

The response of an artificial opal to different polarization states of incident light is quantitatively analyzed by performing Mueller matrix (MM) polarimetry measurements in the transmission geometry. In addition, the wavelength-resolved polarization effects of the transmitted light from the opal are quantitatively investigated especially for the wavelengths lying inside the stop band, at the band edge, outside the stop band and far-outside the stop band. It is observed that the degree of polarization (DOP) of the transmitted light effectively decreases from unity and the polarized component in the transmitted light evolves from linear to slightly elliptical polarization when the wavelength of the linearly polarized incident light goes from inside to outside the stop band. On the other hand, only a small variation in the DOP is observed for circularly polarized incident light with the polarized component in the transmitted light nearly preserving its right-handed circular character. For comparison, the measurement is also done on a solution sample containing monodispersed colloids of the same size. The optical performance of the opal is characterized by calculating the linear, 45° linear, and circular diattenuation parameters from the measured MM elements. For the sake of completeness, the diattenuation parameters of the opal are calculated from the corresponding MM elements for oblique angles of incidence when the incident wavelength falls within the stop band. The same parameters are also quantified from the polarization- and angle-resolved transmission spectral measurements using a spectrophotometer and the one-to-one comparison between the parameters reveals an excellent agreement between the two measurements.