Giant inverse Faraday effect in a plasmonic crystal ring

Circularly polarized electromagnetic wave impinging on a conducting ring with a two-dimensional electron channel generates a circulating DC plasmonic current resulting in an inverse Faraday effect in nanorings. We show that a large ring with periodically modulated width on a nanoscale, smaller or comparable with the plasmonic mean free path, supports plasmon energy bands. When circularly polarized radiation impinges on such a plasmonic ring, it produces resonant DC plasmonic current on a macro scale resulting in a giant inverse Faraday effect. The systems comprised of the concentric variable-width rings ("plasmonic disks") and stacked plasmonic disks ("plasmonic solenoids") amplify the generated constant magnetic field by orders of magnitude.