Numerical simulations of the surface plasmon-assisted photo-magnetic effect in metal-dielectric nanostructures [Invited]

We study numerically plasmonic localization and enhancement of the photo-magnetic excitation in metal-garnet nanostructures with surface plasmons excited at the opposite interfaces of the metallic layer. Contrary to intuitive expectations, the resonance at the metal/air interface results in the highest photo-magnetic excitation efficiency. Our findings highlight the key role of the phase shift between the electric field components inside the garnet layer. A comprehensive analysis of the optical losses reveals the importance of absorption in the photo-magnetic dielectric. These results provide a fruitful perspective for future experiments on metal-dielectric photo-magnetic systems towards all-optical magnetization switching at the nanoscale.