Giant magnetoresistance in NiFe-Ag granular alloys

CoFe–Cu granular alloys: From noninteracting particles to magnetic percolation

CoFe–Cu granular films with ferromagnetic content ranging from 0.10 to 0.33 by volume were prepared by radio frequency sputtering. As-cast samples were rapidly annealed at various temperatures up to 750 °C to promote the segregation of CoFe particles within the metallic matrix. Magnetic and transport properties suggested that this family of samples may be classified into three groups: ~i! below...

Unconventional GMR angular dependence using a compensated ferrimagnet

We have designed a GdCo/Cu/NiFe Giant Magnetoresistance (GMR) trilayer, the magnetoresistance of which does not always depend on the angle between the magnetisations of the electrodes. Using a GdCo ferrimagnetic alloy close to compensation, it was possible to experimentally reach the spin flop field Bsf of the ferrimagnetic layer. Below Bsf , the ferrimagnetic layer behaves as a ferromagnetic l...

Magnetic properties and giant magnetoresistance of magnetic granular Co10Cu90 alloys obtained by direct‐current joule heating

Site-specific measurement of the giant magnetoresistance (GMR) of individual NiFe/Pt multilayers nanowires

As devices shrink, there is a requirement to characterize the magnetic properties of individual inhomogeneous nanosized components. Here the site-specific giant magnetoresistance (GMR) of individual NiFe/Pt multilayer nanowires has been evaluated in the current perpendicular to plane (CPP) geometry using a new in-situ method directly inside a scanning electron microscope (SEM). In this method a...

Domain structures in magnetoresistive granular metals

We have imaged the magnetic domain structure of several heterogeneous CoxAg12x alloys by using scanning electron microscopy with polarization analysis. These images show that extended domain structures exist in both the as-deposited samples and in samples annealed at moderate temperatures. This suggests that a significant fraction of the cobalt in these materials does not contribute to the gian...