Resonances of the magneto-optical intensity effect mediated by interaction of different modes in a hybrid magnetoplasmonic heterostructure with gold nanoparticles

Here we demonstrate a novel magnetoplasmonic heterostructure for efficient control of light. It consists of gold nanoparticles embedded in a thin magnetic film covered with a gold layer pierced with periodic nanoslit array. Unique feature of the proposed structure is that it supports four different types of optical modes in the same frequency range including localized and propagating surface plasmons along with waveguide modes. A peculiar magneto-optical response appears at the frequencies of the mode hybridization. The most important result comes from hybridization of the localized and propagating plasmons leading to a significant increase of the magneto-optical effect intensity.