Example：10.1021/acsami.1c06204 or Chem. Rev., 2007, 107, 2411-2502
Robust formation of skyrmion and skyrmionium in magnetic hemispherical shells and their dynamic switching Physical Review B (IF4.036), Pub Date : 2021-10-25, DOI: 10.1103/physrevb.104.134427 Jaehak Yang, Hyeon-Kyu Park, Gyuyoung Park, Claas Abert, Dieter Suess, Sang-Koog Kim
We explored the variations of the topological magnetic textures of vortices, skyrmions, and skyrmioniums in magnetic elements of hemispherical-shell shape with respect to surface-normal uniaxial magnetic anisotropy constant , Dzyaloshinskii-Moriya interaction (DMI) constant , and shell diameter . For given values of , the combination of and plays a crucial role in the stabilization of those different spin textures. With decreasing , the geometrical confinement of hemispherical shells more significantly affects the stabilization of skyrmions owing to curvature-induced DM-like interaction. This effect is contrastingly dependent on the sign of : skyrmion formation is more favorable for positive values, whereas it is less favorable for negative ones. A quite promising feature is that skyrmions can be stabilized even in the absence of intrinsic DMI for . We also explored characteristic dynamic properties of skyrmions excited by in-plane and out-of-plane oscillating magnetic fields. Similarly to the fundamental dynamic modes found in planar dots, in-plane gyration and azimuthal spin-wave modes as well as out-of-plane breathing modes were found, but additional higher-frequency hybrid modes also appeared due to coupling between radially quantized and azimuthal spin-wave modes. Finally, we found a switching behavior of skyrmion polarity through a transient skyrmionium state using very-low-strength AC magnetic fields. This work provides further physical insight into the static and dynamic properties of skyrmions in curved-geometry nanodots and suggests potential applications to low-power-consumption and ultra-high-density information-storage devices.