Stress controlled magnetic properties of Cobalt nanowires

TL;DR

This study explores how stress influences the magnetic properties of cobalt nanowires embedded in alumina, revealing temperature-dependent magnetization, coercivity, and exchange bias effects, with potential for stress-controlled magnetic tuning.

Contribution

It demonstrates stress-induced control of magnetic anisotropy and uncovers unusual magnetic behaviors in cobalt nanowires at low temperatures, advancing understanding of stress-magnetism interactions.

Findings

Magnetization and coercivity increase below 100 K.

Unusual exchange bias appears below 100 K.

Magnetic properties can be tuned via stress.

Abstract

We investigate the magnetic properties of a composite comprising of ferromagnetic Cobalt nanowires embedded in nanoporous anodized alumina template. We observe unusual increase in, the saturation magnetization and the coercive field, of the nanowires below 100 K. We also report the appearance of an unusual exchange bias effect in nanowires below 100 K. We argue our results can be understood on the basis of a competition between different magnetic energy scales induced by significant stresses acting on the nanowires at low temperatures. The composite behaves as an effective medium in which the magnetic anisotropy of nanowires can be conveniently controlled via stress on the nanowires.