Spin dependent scattering of a domain-wall of controlled size

TL;DR

This study investigates how the size of a domain wall in Co nanowires affects magnetoresistance, revealing spin-dependent scattering contributions when the wall is compressed below the spin diffusion length.

Contribution

It demonstrates controlled domain wall size manipulation in Co nanowires and links this to specific spin-dependent scattering effects in magnetoresistance.

Findings

Additional magnetoresistance contribution observed with compressed domain walls.

Spin-dependent scattering occurs when domain wall thickness is below the spin diffusion length.

Controlled domain wall size influences magnetoresistance behavior.

Abstract

Magnetoresistance measurements in the CPP geometry have been performed on single electrodeposited Co nanowires exchange biased on one side by a sputtered amorphous GdCo layer. This geometry allows the stabilization of a single domain wall in the Co wire, the thickness of which can be controlled by an external magnetic field. Comparing magnetization, resistivity, and magnetoresistance studies of single Co nanowires, of GdCo layers, and of the coupled system, gives evidence for an additional contribution to the magnetoresistance when the domain wall is compressed by a magnetic field. This contribution is interpreted as the spin dependent scattering within the domain wall when the wall thickness becomes smaller than the spin diffusion length.