Fachgruppe Nanostrukturierte Materialien    

Using the ultralow damping NiMnSb half-Heusler alloy patterned into vortex-state magnetic nanodots, we demonstrate a concept of nonvolatile memory controlled by the frequency. A perpendicular bias magnetic field is used to split the frequency of the vortex core gyrotropic rotation into two distinct frequencies, depending on the sign of the vortex core polarity inside the dot. A magnetic resonance force microscope and microwave pulses applied at one of these two resonant frequencies allow for local and deterministic addressing of binary information (core polarity).