Optical Response of a Hematite Coating: Ellipsometry Data versus Fourier-Based Computations

E. Couka, F. Willot, P. Callet, D. Jeulin
2015 Advanced Science Engineering and Medicine  
The optical properties of a hematite-epoxy coating are predicted numerically and compared with ellipsometry measurements. The highly-heterogeneous dispersion of nanocubic hematite particles in the epoxy resin is simulated using a previously developed two-scales random model. The local anisotropic permittivity tensor of hematite particles, and that of the epoxy, are estimated by ellipsometry measurements carried out on a macroscopic hematite and epoxy samples. Fourier-based methods using a
more » ... ete" Green operator are used to treat complex permittivities. They predict the effective and local electric displacement field in the quasi-static approximation. The former is close to two estimates based on the Hashin-Shtrikman bounds and a self-consistent approximation. Good agreement is found between experimental data and FFT computations in the whole range of the visible spectrum.
doi:10.1166/asem.2015.1790 fatcat:raie5nxg45gtrnngxbxyuofsii