Magneto-transport properties of CoFeSiB/(Co, CoPtRh) multilayer microwires

The magneto-impedance (MI) effect in amorphous magnetic materials and its sensitivity to stress has lead to many proposed applications such as traffic control, automotive industry, biomedical sensors, etc. In the case of amorphous wires many approaches have been tried to improve the MI effect through controlling the transverse magnetic permeability and skin effect, including annealing, ion irradiation, patterning, etc. Coating of microwires with layers of non-magnetic and magnetic cylindrical coatings induces a bi-phase character, beneficial for devices based on asymmetrical magnetoimpedance. The soft or hard magnetic materials deposited on the glass-coated microwires determine changes in the magnetic behaviour of these materials due to the contribution of the nature of the deposited material, its structure, and of the induced supplementary stresses. The aim of this paper is to present results on the effect of deposition of Co and CoPtRh layers and of temperature on the magnetic and magneto-transport properties of nearly zero magnetostrictive CoFeSiB glass-coated microwires. Considering the importance of the role of stresses and of temperature it is expected that the combination of both will strongly affect the magnetic behaviour of the composite magnetic multilayer microwires.