Performance analysis of metallo-dielectric optical filters designed using dispersion relations

We present an experimental validation of an analytical approach to predict the spectral response of multilayer metallo-dielectric structures, with applications in the efficient design of bandpass optical filters. Instead of relying on trial-and-error methods, our approach—referred to as the dispersion relation method—is based on intrinsic physical relations, potentially resulting in a significant reduction in time and resources during the design and optimization process. In our previous work, we illustrated that characteristics of the band structure revealed by the dispersion relation can serve as reasonable estimates for the center wavelengths and bandwidths for finite multilayer structures, as obtained from numerical simulations. In this work, we verify those conclusions with experimental results from metallo-dielectric optical filters prepared via magnetron sputtering. Structures using different metals including Ag, Au, and Al are investigated. We show good agreement between spectral response predictions derived from dispersion relations, numerical simulations using the transfer matrix method, and experimental transmittance spectra of the fabricated structures. Considering this experimental validation, the analytical approach based on dispersion relations can offer an accurate and efficient method for designing metallo-dielectric filter structures. Our approach facilitates the selection of geometric parameters for fabrication and provides valuable insight into the optical characteristics of such structures.