Current- and field-driven magnetic antivortices for nonvolatile data storage

We demonstrate by micromagnetic simulations that magnetic antivortices are potential candidates for fast nonvolatile data-storage elements. These storage elements are excited simultaneously by alternating spin-polarized currents and their accompanying Oersted fields. Depending on the antivortex-core polarization $p$ and the orientation of the in-plane magnetization $c$ around the core, the superposition of current and field leads to either a suppression of gyration (logical “zero”) or an increased gyration amplitude (logical “one”). Above an excitation threshold the gyration culminates in the switching of the antivortex core. The switching can be seen as a $cp$-dependent writing of binary data, allowing to bring the antivortex into a distinct state. Furthermore a read-out scheme using an inductive loop situated on top of the element is investigated.