Tailoring magnetic vortices of dipolar coupled nanoelements

We report a theoretical study of the magnetic profiles of vortex pairs of dipolar coupled Fe nanocylinders. We consider pairs of identical and coaxial 21nm height Fe circular nanocylinders with the diameter values ranging from 81nm to 129nm. We show that, even though each isolated nanocylinder holds a vortex at remanence, the dipolar interaction may inhibit the formation of vortices for small values of the nanocylinders' distance. For moderate values of the nanocylinders' distance, the formation of opposite chirality vortex pairs is favored. We show that the vortex locations, the vortex pair magnetic pattern, and the dipolar field and local field profiles may be tailored using moderate external field values along preparation routes parallel and perpendicular to the Fe uniaxial anisotropy easy axis.