Single vortex core recording in a magnetic vortex lattice

Abstract

We investigated the reversal characteristics of magnetic vortex cores in a two dimensional assembly of magnetic vortices. The vortex lattice was created by film deposition of 30-nm-thick permalloy onto large arrays of self-assembled spherical SiO2-particles with a diameter of 330 nm. The vortex core reversal was investigated by employing a write/read tester. This device uses a state-of-the-art magnetic recording head of a hard disc drive, which allows imaging as well as applying a local magnetic field pulse to individual vortices. The successful writing and reading of individual vortex cores is demonstrated, including a switching map, which indicates the switching behavior dependent on the relative position of the field pulse with respect to the vortex core.