- Scanning electron microscopy polarization analysis images of wide (a) and the narrow (c) Ferromagnetic rings, with corresponding micromagnetic simulations of the wide (b) and the narrow (d) ring, showing the vortex- and transverse-type domain walls.
Understanding and controlling the magnetic properties of small ferromagnetic elements is a major challenge in the rapidly evolving field of nanoscale science. These structures not only allow for the investigation of fundamental physical properties but also have important applications in, for example, magnetic memory and sensor devices. One key issue is to understand and control the magnetic switching precisely, and to achieve this well defined and reproducible remnant states are required, as well as a simple and reproducible switching process. A geometry that fulfils these criteria is the ring geometry, and in particular narrow ferromagnetic rings, which have recently become the focus of intense interest.