Enhancing magneto-optical coupling and scattering from magnetic vortices by optical polarization texturing

Magnetic textures offer a route toward photonic functionality in which electromagnetic fields are controlled not only by material composition and geometry but also by the internal magnetic configuration. Conversely, spatial texturing of these fields is a qualitatively new tool to increase the effective coupling strength to magnetic matter and to act on the the vortex topology and magnetic dynamics. Here, we investigate the coupling and scattering of structured electromagnetic fields by a magnetic vortex, focusing on how spatially non-collinear magnetization governs polarization conversion, electromagnetic energy flow, and magnetization dynamics. We develop a spherical rigorous coupled-wave method that incorporates the spatially dependent anisotropic magnetic permeability associated with the vortex texture. The calculations show that the off-diagonal components of the magnetic susceptibility mediate conversion into complementary polarization channels that are absent from the incident field. The generated fields exhibit pronounced spatial localization associated with the vortex magnetization profile and support a nonzero azimuthal component of electromagnetic energy flow. A comparison between linearly and radially polarized illumination reveals an approximately one-order-of-magnitude difference in the scattered fields amplitudes due to polarization texturing, demonstrating the importance of spatial overlap between the incident field and the anisotropic magnetic response. The back-action on the magnetic vortex dynamics is quantitatively demonstrated by numerical simulations for the inverse Faraday effect due to the rectification of structured effective-field excitation. It is shown that polarization textured optical fields can drive vortex-core precession and, at sufficiently strong excitation, reverse the core polarity and chirality on nanosecond time scale.