Analysis of surface plasmon resonance modes in a metal-dielectric multilayer structure with an adhesive layer using finite difference frequency domain (FDFD) method

The optical response of a metal-dielectric multilayer structure consisting of a hybrid Au/Ag grating and an adhesive layer sandwiched between two dielectric layers has been analyzed using the Finite Difference Frequency Domain (FDFD) method. We observed two surface plasmon resonance (SPR) modes, one in the visible and the other in the ultraviolet region due to the localization of the field at the dielectric-metal interface. Among the other well-known attributes that affects the SPR characteristics, the structural and optical properties of the adhesive layer are crucial in determining the SPR peak/dip intensity profile even though the SPR wavelength is relatively unchanged. Hence, we show a direct application of FDFD numerical analysis of the multimode SPR dependence on the adhesive layer properties in dielectric-metal-grating-dielectric layers, which is useful for more precise experimental fabrication of optical sensors.