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Magnetic skyrmionium can be used as a nanometer-scale non-volatile information carrier, which shows no skyrmion Hall effect due to its special structure carrying zero topological charge. Here, we report the static and dynamic properties of an isolated nanoscale skyrmionium in a frustrated magnetic monolayer, where the skyrmionium is stabilized by competing interactions. The frustrated skyrmionium has a size of about 10 nm, which can be further reduced by tuning perpendicular magnetic anisotropy or the magnetic field. It is found that the nanoscale skyrmionium driven by the damping-like spin-orbit torque shows directional motion with a favored Bloch-type helicity. A small driving current or magnetic field can lead to the transformation of an unstable Néel-type skyrmionium to a metastable Bloch-type skyrmionium. A large driving current may result in the distortion and collapse of the Bloch-type skyrmionium. Our results are useful for the understanding of frustrated skyrmionium physics, which also provide guidelines for the design of spintronic devices based on topological spin textures. [ABSTRACT FROM AUTHOR]

Highlights • Prepared Nd-Fe-B films with perpendicular magnetic anisotropy at lower temperature. • Improved magnetic anisotropy and c-axis orientation by Tb additions. • Demonstrated correlations between as-deposited amorphous crystallized films. • Revealed the origination of crystallographic properties of annealed Nd-Fe-B films. Abstract Nd-Fe-B films with perpendicular magnetic anisotropy are important for various applications. Most common process to prepare Nd-Fe-B thin films with perpendicular magnetic anisotropy is the heteroepitaxy process. Here, Nd-Fe-B thin films with perpendicular magnetic anisotropy were prepared by a two-step process. Amorphous and magnetically soft thin films were first deposited. Crystallized, magnetic hard thin films were obtained by rapid thermal annealing of the as-deposited films. A clear correlation between perpendicular magnetic anisotropy of annealed state and the domain configuration in the as-deposited state was noticed. Films prepared without substrate heating, with additions of Tb show perpendicular coercivity which is larger than 24 kOe. [ABSTRACT FROM AUTHOR]