Anisotropic magnetoresistance effect in sub-micron nickel disks

作者：Wren T^*; Kazakova O

来源：Journal of Applied Physics, 2015, 117(17): 17E134.

DOI：10.1063/1.4918967

The hysteretic transport properties of vortex states in sub-micron nickel disks are measured using the anisotropic magnetoresistance (AMR) effect and correlated with the magnetization state of the disks using in-situ magnetic force microscopy and micromagnetic modelling. The magnetoresistance behavior is described by a simple AMR model; however, the nucleation and annihilation fields of the vortex state differ when the magnetic field is applied parallel (0 degrees) or perpendicular (90 degrees) to the applied current within the sample plane. In the 0 degrees orientation, the vortex magnetoresistance behaves similar to that reported in the literature. However, in the 90 degrees orientation, the vortex nucleates and annihilates at lower applied fields than in the 0 degrees orientation. Moreover, in the latter orientation, the annihilation process occurs in a two-step transition. This difference is attributed to the effect of the inhomogeneous current distribution within the magnetic disk.

• 出版日期2015-5-7