360{\deg} Domain Walls: Stability, Magnetic Field and Electric Current Effects

TL;DR

This study experimentally investigates the formation, stability, and annihilation of 360-degree magnetic domain walls in thin film wires, revealing how wire width, magnetic fields, and electric currents influence their behavior.

Contribution

It provides new experimental insights into the conditions for stable 360-degree domain walls and their response to magnetic fields and electric currents.

Findings

Reproducible 360DW formation occurs at intermediate wire widths.

Annihilation fields are higher than dissociation fields, consistent with micromagnetic models.

360DW annihilation can be achieved through current pulsing.

Abstract

The formation of 360{\deg} magnetic domain walls (360DWs) in Co and Ni80Fe20 thin film wires was demonstrated experimentally for different wire widths, by successively injecting two 180{\deg} domain walls (180DWs) into the wire. For narrow wires (less than 50 nm wide for Co), edge roughness prevented the combination of the 180DWs into a 360DW, and for wide wires (200 nm for Co) the 360DW collapsed, but over an intermediate range of wire widths, reproducible 360DW formation occurred. The annihilation and dissociation of 360DWs was demonstrated by applying a magnetic field parallel to the wire, showing that annihilation fields were several times higher than dissociation fields in agreement with micromagnetic modeling. The annihilation of a 360DW by current pulsing was demonstrated.