Three-Dimensional Dynamics of a Magnetic Hopfion Driven by Spin Transfer Torque.

  title={Three-Dimensional Dynamics of a Magnetic Hopfion Driven by Spin Transfer Torque.},
  author={Yizhou Liu and Wentao Hou and Xiufeng Han and Jiadong Zang},
  journal={Physical review letters},
  volume={124 12},
Magnetic hopfion is a three-dimensional (3D) topological soliton with novel spin structure that would enable exotic dynamics. Here, we study the current-driven 3D dynamics of a magnetic hopfion with a unit Hopf index in a frustrated magnet. Attributed to the spin Berry phase and symmetry of the hopfion, the phase space entangles multiple collective coordinates, thus the hopfion exhibits rich dynamics including longitudinal motion along the current direction, transverse motion perpendicular to… 

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