ABSTRACT

The possibility of concentrating and manipulating light at unprece-

dentedly low size scales by means of surface electromagnetic waves

such as surface plasmon polaritons (SPPs) or localized surface

plasmons (LSPs), well below the diffraction limit, opens a strikingly

broad spectrum of fundamental and practical applications such as

plasmonic circuits, plasmonic lenses, light trapping, biosensors, and

cancer treatment, among many others. Nevertheless, for many of

these applications it is important to have external control of the

propagation of such plasmonic resonances, for example, using exter-

nal magnetic fields. In this chapter we will discuss how adequately

inserting magneto-optically active metals such as ferromagnetic

transition metals in systems with plasmonic properties such as thin

films, multilayers, and nanostructures imparts to them a strong

sensitivity to external magnetic fields. In turn these systems exhibit

also a remarkable increase of the magneto-optical activity due to

interaction of the strong electromagnetic fields generated by the

plasmonic excitations and the magneto-optically active materials.