Giant Magnetoresistance and Hysteresis Phenomena in CoFe/Cu Superlattices with Highly Perfect Crystallographic Texture

Resumo

This paper presents the results of the investigation of the structure and magnetoresistive properties of [Co₉₀Fe₁₀/Cu]_n superlattices deposited on (Ni₈₀Fe₂₀)₆₀Cr₄₀ and Ta/(Ni₈₀Fe₂₀)₆₀Cr₄₀ buffer layers by magnetron sputtering. Our study has found that a Ta sublayer added to the (Ni₈₀Fe₂₀)₆₀Cr₄₀ buffer layer increases the degree of perfection of the 〈111〉 texture. This leads to a substantial decrease in the magnetoresistance hysteresis. The optimization of the composition of multilayered structure allowed us to obtain the superlattice with the relative magnetoresistance magnitude, which at room temperature reaches 81% and, at liquid helium temperature, exceeds 160%. The studied superlattices exhibited high temperature stability.