Dynamical pinning of domain wall in magnetic nanowire induced by Walker breakdown

TL;DR

This paper investigates how Walker breakdown causes dynamical pinning of domain walls in magnetic nanowires, revealing a counterintuitive decrease in transmission probability at high magnetic fields through simulations and experiments.

Contribution

It demonstrates that Walker breakdown induces dynamical pinning of domain walls, providing a new understanding of domain wall dynamics in rough nanowires.

Findings

Transmission probability drops after a threshold magnetic field.

Walker breakdown causes dynamical pinning in rough nanowires.

Simulation semi-quantitatively explains experimental results.

Abstract

Transmission probability of a domain wall through a magnetic nanowire is investigated as a function of the external magnetic field. Very intriguing phenomenon is found that the transmission probability shows a significant drop after exceeding the threshold driving field, which contradicts our intuition that a domain wall is more mobile in the higher magnetic field. The micromagnetics simulation reveals that the domain wall motion in the wire with finite roughness causes the dynamical pinning due to the Walker breakdown, which semi-quantitatively explains our experimental results.