Twisting Polarization‐Tunable Subdiffraction‐Limited Magnetization through Vectorial Beam Coupling

Abstract

All‐optical control of magnetization vectors is considered as a powerful solution that empowers the development of multifunctional integrated optomagnetic devices. The interaction between vectorial light and magnetism has recently experienced a surge of interest due to its prominent ability to steer the magnetic polarization orientations and spatial textures within the subwavelength domain, which, however, usually requires complex wavefront coding optimizers or arduous material fabrication procedures. Herein, an optimization‐free all‐vectorial‐optical strategy for first realizing spatially twist‐controllable and successively polarization‐tunable magnetization at the subdiffraction scale through the inverse Faraday effect is conceived and demonstrated. This facile method relies on the coherent coupling of double crossed azimuthally polarized doughnut‐Gaussian vortex beams in a single optically configured geometry. It is found that both the magnetic twisting manifolds and polarization states, rotating from perpendicular (longitudinal), via hybrid (3D) to in‐plane (transverse) orientations, can be on‐demand mediated by judiciously tuning the crossing angles. It is further unraveled that the orbital angular momenta associated with topological charges of the vortex beams can be viewed as a vital knob to energetically maneuver magnetic twisting and guide magnetization switching. It is believed that the proposed route and presented findings are not only of great theoretical implication in twistronics and optomagnetic topology but also of considerable technological significance in multidimensional high‐density and low‐energy consumption optomagnetic storage and engineering of magnetic topologic materials.

Keywords

• inverse Faraday effect
• magnetization reversal
• optomagnetic effects
• orbital angular momentum
• vectorial beams