Facile determination of matter’s optical properties by combining Monte Carlo and Berreman 4x4 matrix approaches: Dispersion in nematic and emerging ferroelectric nematic liquid crystals

Abstract

Determination of material and optical properties in structured films and fluids, e.g., refractive index and material thickness, usually requires special optical geometries and instruments. This prevents one from studying optical properties especially in soft matter systems with nonuniform hierarchical and orientational structures. Here we develop a data measurement and analysis scheme by combining Monte Carlo and Berreman 4x4 matrix approaches for obtaining the dispersion of refractive index, material thickness, and the optical anisotropy from a single shot of simple transmission or reflection spectroscopy data at a time scale of seconds. We show the validity of the method by determining Cauchy coefficients and sample thickness of the well-known reference materials of both isotropic toluene solution and anisotropic material of a nematic liquid crystal (4-cyano-4′-pentyl biphenyl). This enables us to further investigate the unknown optical properties of an emerging ferroelectric nematic material, the so-called RM734.