Spin valves based on amorphous ferrimagnetic Gd–Co films

Abstract

Multilayer Gd–Co/Co/Cu/Co structures were prepared by magnetron sputtering. An analysis of the magnetic and resistive properties allows us to classify these structures among spin valves which demonstrate the giant magnetoresistance effect. The mechanism of the sign reversal of giant magnetoresistance with changing thickness of the Co layer, which is exchange coupled with the ferrimagnetic Gd–Co layer, has been interpreted.