PERPENDICULAR GIANT MAGNETORESISTANCE OF MICROSTRUCTURED PILLARS IN MAGNETIC MULTILAYERS

We have fabricated pillar-like microstructures of Fe/Cr and Co/Cu magn etic multilayers and measured the giant magnetoresistance effect with the current perpendicular to the multilayer plane. The perpendicular g iant magnetoresistance effect was determined as a function of temperat ure from 4K to 300 K. For both Fe/Cr and Co/Cu multilayers we find, at low temperature, magnetoresistance effects of the order of 100%. The Fe/Cr pillars show a pronounced decrease with temperature of the magne toresistance, while for Co/Cu the temperature dependence is much weake r. This different behaviour is caused by the different temperature dep endence of the spin-dependent scattering; in the case of Co/Cu, we pre sent results of a quantitative analysis of the temperature dependence using a resistance model of Fert and Campbell, originally proposed for magnetic alloys [1].