Perpendicular giant magnetoresistance of microstructured pillars in magnetic multilayers

Pillar-like microstructures of Fe/Cr and Co/Cu magnetic multilayers have been fabricated and the giant magnetoresistance effect measured with the current perpendicular to the multilayer plane. The perpendicular giant magnetoresistance effect was determined as a function of temperature from 4-300K. For both Fe /Cr and Co/Cu multilayers were found, at low temperature, magnetoresistance effects of approx100%. The Fe/Cr pillars showed a pronounced decrease with temperature of the magnetoresistance, while for Co/Cu the temperature dependence was much weaker. This different behaviour is caused by the different temperature dependence of the spin-dependent scattering; in the case of Co/Cu, results are presented of a quantitative analysis of the temperature dependence using a resistance model of Fert and Campbell (1976), originally proposed for magnetic alloys.