Near-field interaction between domain walls in adjacent Permalloy nanowires

TL;DR

This study experimentally demonstrates the magnetostatic interaction between domain walls in adjacent Permalloy nanowires, revealing how their interaction influences pinning strength and potential for non-contact data storage applications.

Contribution

It provides the first detailed experimental analysis of near-field interactions between domain walls in adjacent nanowires, showing how these interactions can be controlled without disturbing the domain wall structure.

Findings

Pinning strength depends on wire separation, up to 93 Oe.

Interactions are fully described by magnetic charge distribution.

Domain walls remain rigid despite pinning forces.

Abstract

The magnetostatic interaction between two oppositely charged transverse domain walls (DWs)in adjacent Permalloy nanowires is experimentally demonstrated. The dependence of the pinning strength on wire separation is investigated for distances between 13 and 125 nm, and depinning fields up to 93 Oe are measured. The results can be described fully by considering the interaction between the full complex distribution of magnetic charge within rigid, isolated DWs. This suggests the DW internal structure is not appreciably disturbed by the pinning potential, and that they remain rigid although the pinning strength is significant. This work demonstrates the possibility of non-contact DW trapping without DW perturbation and full continuous flexibility of the pinning potential type and strength. The consequence of the interaction on DW based data storage schemes is evaluated.