RC-circuit-like dynamic characteristic of the magnetic domain wall in ferromagnetic nanowires

TL;DR

This paper demonstrates that magnetic domain walls in ferromagnetic nanowires exhibit RC-circuit-like dynamics under perpendicular magnetic field pulses, enabling high-speed motion without Walker breakdown, with potential spintronic applications.

Contribution

It introduces a novel RC-circuit-like model to explain the dynamic behavior of magnetic domain walls driven by perpendicular magnetic fields in nanowires.

Findings

Domain walls can be driven faster than 300 m/s without Walker breakdown.

Magnetic domain wall dynamics can be modeled by charging and discharging behaviors.

The RC-like model offers new insights for spintronic device design.

Abstract

We have investigated dynamic behaviors of the magnetic domain wall under perpendicular magnetic field pulses in ferromagnetic nanowires using micromagnetic simulations. It has been found that the perpendicular magnetic field pulse can trigger the magnetic domain wall motion, where all the field torques are kept to be on the plane of nanowire strip. The magnetic domain wall speed faster than several hundreds meters per second is predicted without the Walker breakdown for the perpendicular magnetic driving field stronger than $200~\mathrm{mT}$. Interestingly, the dynamic behavior of the moving magnetic domain wall driven by perpendicular magnetic field pulses is explained by charging- and discharging-like behaviors of an electrical RC-circuit model, where the charging and the discharging of "magnetic charges" on the nanowire planes are considered. The concept of the RC-model-like dynamic characteristic of the magnetic domain wall might be promising for spintronic functional device applications based on the magnetic domain wall motion.