Mirostructured permalloy ellipses having purposely designed multi-domain configurations were investigated. The samples were fabricated using e-beam lithography through a lift-off process. The magnetoresistance measurements were carried out with a constant dc sensing current under the external magnetic field applied along the short axis. The magnetoresistance curves manifest characteristic features in accordance with the specific domain configurations. Step-like/kink features were observed on the ellipses with cross-tie wall/ two-vortex configuration and step-like plus kink magnetorsistance curve was found on the ellipse with cross-tie wall combining with twovortex structure. A magnetic force microscopy and a micromagnetic simulation were employed to support these results.
Journal of Magnetism and Magnetic Materials, 310(2) Part3: e672-e674