Driving large-velocity propagation of ferromagnetic pi/2 domain walls in nanostripes of cubic-anisotropy materials

摘要

We study the externally-driven motion of the domain walls (DWs) of the pi/2 type in (in-the-plane ordered) nanostripes with crystalline cubic anisotropy. Such DWs are much narrower than the transverse and vortex pi DWs in the soft-magnetic nanostripes while they propagate much faster, thus enabling dense packing of magnetization domains and high-speed processing of the many-domain states. The viscous current-driven motion of the DW with velocity above 1000 m s(-1) under the electric current of the density similar to 10(12) A m(-2) is predicted to take place in the nanostripes of the magnetite. Also, the viscous motion with the velocity above 700 m s(-1) can be driven by the magnetic field according to our solution to a 1D analytical model and micromagnetc simulations. Such huge velocities are achievable in the nanostripes of very small cross-sections (only 100 nm width and 10 nm thickness). The fully stress-driven propagation of the DW in the nanostripes of cubic magnetostrictive materials is predicted as well. The strength of the DW pinning to the stripe notches and the thermal stability of the magnetization during the current flow are addressed.