Crossed-ratchet effects and domain wall geometrical pinning

Crossed-ratchet effects for magnetic domain wall motion.

We study both experimentally and theoretically the driven motion of domain walls in extended amorphous magnetic films patterned with a periodic array of asymmetric holes. We find two crossed-ratchet effects of opposite sign that change the preferred sense for domain wall propagation, depending on whether a flat or a kinked wall is moving. By solving numerically a simple phi(4) model we show tha...

The effect of geometrical confinement and chirality on domain wall pinning behavior in planar nanowires

Shift registers based on magnetic domain wall ratchets with perpendicular anisotropy.

The movement of magnetic domain walls can be used to build a device known as a shift register, which has applications in memory and logic circuits. However, the application of magnetic domain wall shift registers has been hindered by geometrical restrictions, by randomness in domain wall displacement and by the need for high current densities or rotating magnetic fields. Here, we propose a new ...

Effective pinning energy landscape perturbations for propagating magnetic domain walls

The interaction between a magnetic domain wall and a pinning site is explored in a planar nanowire using micromagnetics to reveal perturbations of the pinning energetics for propagating domain walls. Numerical simulations in the high damping 'quasi-static' and low damping 'dynamic' regimes are compared and show clear differences in de-pinning fields, indicating that dynamical micromagnetic mode...

Correlation between spin structure oscillations and domain wall velocities

Magnetic sensing and logic devices based on the motion of magnetic domain walls rely on the precise and deterministic control of the position and the velocity of individual magnetic domain walls in curved nanowires. Varying domain wall velocities have been predicted to result from intrinsic effects such as oscillating domain wall spin structure transformations and extrinsic pinning due to imper...