Magnetoresistance in Nanostructured Co-Ag Prepared by Mechanical- Alloying

Authors

J.M.D. Coey, Trinity College, Dublin, Ireland
A.J. Fagan, Trinity College, Dublin, Ireland
Ralph Skomski, University of Nebraska-LincolnFollow
J. Gregg, University of Oxford
K. Ounadjela, Institut Lebel, C.N.R.S. Strasbourg, 4 Rue Blaise Pascal, 67070 Strasbourg - CEDEX, France
S.M. Thompson, University of York, Heslington, York, UK

Date of this Version

March 1994

Comments

Published in IEEETRANSACTIONS ON MAGNETICS, VOL. 30, NO. 2, MARCH 1994.

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 the 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.