Nanostructured magnetic materials provide an efficient tool for light manipulation on sub-nanosecond and sub-micron scales, and allow for the observation of the novel effects which are fundamentally impossible in smooth films. For many cases of practical importance, it is vital to observe the magneto-optical intensity modulation in a dual-polarization regime. However, the nanostructures reported on up to date usually utilize a transverse Kerr effect and thus provide light modulation only for p-polarized light. We present a concept of a transparent magnetic metasurface to solve this problem, and demonstrate a novel mechanism for magneto-optical modulation. A 2D array of bismuth-substituted iron-garnet nanopillars on an ultrathin iron-garnet slab forms a metasurface supporting quasi-waveguide mode excitation. In contrast to plasmonic structures, the all-dielectric magnetic metasurface is shown to exhibit much higher transparency and superior quality-factor resonances, followed by a multifold increase in light intensity modulation. The existence of a wide variety of excited mode types allows for advanced light control: transmittance of both p- and s-polarized illumination becomes sensitive to the medium magnetization, something that is fundamentally impossible in smooth magnetic films. The proposed metasurface is very promising for sensing, magnetometry and light modulation applications.

All-dielectric metasurfaces have been attracting much attention. Low optical losses and a huge variety of optical modes provide unique possibilities for light manipulation at the nanoscale. Recent studies showed that the magneto-optical effects in such metasurfaces are enormously enhanced. Moreover, it is possible to observe novel magneto-optical effects that are absent in smooth films. Excitation of particular photonic resonances makes it possible to design the magneto-optical interaction by the metasurface design. This opens up broad opportunities for magneto-photonic metasurface applications, including optomagnetism, light modulation, sensing, magnetometry, etc.

We report the enhancement of the magneto-optical Faraday effect in a two-dimensional magnetoplasmonic grating with a square lattice. The structure consists of dielectric magnetic Bi-substituted iron garnet film with low thickness (100 nm) coated by a perforated gold layer. Enhancement of the Faraday rotation by about 2 times is shown experimentally and theoretically despite the suppression of the waveguiding modes. This happens primarily through excitation of surface plasmon polaritons propagating at the Au-garnet interface in two orthogonal directions along lattice vectors of the plasmonic grating.

We propose an approach for wavelength-selective excitation of perpendicular standing spin waves by optical guided modes in a magnetic dielectric film. TM-polarized guided waves with elliptical polarization induce an effective magnetic field due to the inverse transverse magneto-optical Kerr effect (ITMOKE). The ITMOKE is similar to the inverse Faraday effect, except for the induced magnetic field direction that is oriented in the film plane perpendicular to guided-mode propagation. Switching between different guided modes by tuning the wavelength or angle of the laser pulse significantly modifies the spatial distribution of the induced ITMOKE field and, therefore, selectively launches the standing spin-wave modes of different orders. Consequently, one may perform a tunable optical excitation of a certain spin-wave mode via a femtosecond laser pulse of the corresponding wavelength. The proposed approach broadens the spin-wave manipulation capabilities via optical means.

All-dielectric nanostructures provide a unique low-loss platform for efficiently increasing light-matter interaction via excitation of the localized or propagating optical modes. Here, we report on the transverse magneto-optical Kerr effect enhancement in an all-dielectric metasurface based on a two-dimensional array of Si nanodisks on a cerium substituted dysprosium iron garnet thin film. We observed up to 15% light intensity modulation under TM modes excitation. The observed magneto-optical effect is nearly independent of the rotation of the light incidence plane with respect to the metasurface. Being compatible with conventional semiconductor technology, our structure holds promise for device applications, such as light modulators, magnetic and chemical sensors.