Construction of 1D Vortex Chain Using a Chiral Nanostructure.

The construction and control of high-order coupled vortices are a significant challenge for promoting the application of magnetic vortices. Thus far, only double-coupled vortices have been produced and modulated in some ferromagnetic nanostructures. Here, an effective approach is provided to obtain a high-order coupled vortex structure by using a chiral nanostructure. Double-vortex, triple-vortex, and n-vortex chains can be successfully constructed using structured Fe4N nanostrips and bias nanomagnets. The designed chiral nanostructure cannot only control the transport and hybridization of vortices but also modulate the domain walls of the vortex chain for spin wave (SW) propagation. At the exciting frequency of 1.2 GHz, the SW propagates along the domain walls formed in the vortex chain. Upon increasing the frequency to 5.0 GHz, the SW gradually spreads from the domain walls into domains. This technique will present a new perspective for the design and application of magnetic vortex-based devices.