  Here we demonstrate a novel smart magnetoplasmonic heterostructure for
efficient control of light. It consists of gold nanoparticles embedded in a
thin magnetic film covered with a gold layer pierces 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 prominent result comes from hybridization of the
localized and propagating plasmons leading to a significant increase of the
magneto-optical intensity effect.
