Enhanced reflectivity change and phase shift of polarized light. Double parameter multilayer sensor

Herein, the concept of point of darkness based on polarized light phase difference and absorption of light is demonstrated by simulations using low refractive index and extinction coefficient semiconductor and dielectric, and high refractive index nonoxidizing metal multilayer thin film structures. Several multilayer sensor configurations show great sensitivity to thickness and refractive index variation of the detectable material by measuring the reflectivity ratio $\Psi$ and phase shift $\Delta$. Focus is on such multilayers, which have sensitivity to both parameters ($\Psi$, $\Delta$) in the visible spectral range, thus opening the possibility for further research on a new biomedical sensor development with enhanced double parameter sensing. (© 2021 Wiley‐VCH GmbH)