Controlling the scattering of light with magnetic textures*

We explored the use of a magnetic film of Y₃Fe₅O₁₂ for steering light with mesoscale magnetic textures. Combining Kerr microscopy with magneto-optical diffractometry, we have investigated the link between the magnetic domain structure of an otherwise unpatterned magnetic film and the resulting scattering pattern of the transmitted light.
The sample can present a periodic stripe-like magnetic domain structure at remanence. When linearly polarized light is transmitted through the film, the periodicity in the out-of-plane magnetization component can effectively behave as a magneto-optical grating, giving rise to magnetic Bragg peaks, in good agreement with Kerr microscopy data. By further applying dc and/or ac magnetic fields, thus controlling the spatial-temporal evolution of the magnetic domain texture, the scattering pattern of the light is also correspondingly affected. These results serve as a cornerstone study for the design of planar devices with magnetically-reconfigurable optical functionalities.