Resonant enhancement of the transverse magneto-optical effect in opal/cobalt/silver plasmonic heterostructures

Magneto-optical effects in metal–dielectric nanostructured materials based on opal films coated with a thin cobalt/silver nanolayer, whose surface has a close-packed hexagonal lattice of metal nanohemispheres and nanoholes, have been investigated. It has been demonstrated experimentally and theoretically that a wide spectrum of modes of propagating surface plasmon polaritons is excited in such a system, which leads to a resonant enhancement of the magneto-optical effect in the Voigt geometry.