Magnetoresistance in nanostructured Co-Ag prepared by mechanical-alloying

Author

Coey, J.M.D. ; Fagan, A.J. ; Skomski, R. ; Gregg, J. ; Ounadjela, K. ; Thompson, S.M.

Author_Institution

Dept. of Pure & Appl. Phys., Trinity Coll., Dublin, Ireland

Volume

30

Issue

2

fYear

1994

fDate

3/1/1994 12:00:00 AM

Firstpage

666

Lastpage

668

Abstract

Fine cobalt and silver powders have been ball-milled to yield a granular solid of composition Co₃₀Ag₇₀ in the form of coarse powder. The material is an intimate mixture of grains of fcc Co in a silver matrix. The cobalt is in the single-domain size range, and samples exhibit coercivity (0.07 T at 296 K) and unusual thermomagnetic effects, including field-induced unidirectional anisotropy. There is a large, isotropic negative magnetoresistance, which exceeds 10% at 4.2 K

Keywords

cobalt alloys; coercive force; ferromagnetic properties of substances; granular materials; induced anisotropy (magnetic); magnetic anisotropy; magnetoresistance; mechanical alloying; nanostructured materials; powder metallurgy; silver alloys; 296 K; 4.2 K; Co₃₀Ag₇₀; FCC Co grains; ball-milling; coarse powder; coercivity; field-induced unidirectional anisotropy; granular solid; mechanical-alloying; nanostructured Co-Ag; negative magnetoresistance; single-domain size; thermomagnetic effects; Alloying; Cobalt; Electrons; Magnetic materials; Magnetization; Magnetoresistance; Physics; Powders; Silver; Solids;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.312370

Filename

312370