Blocking effect of Mn diffusion in NiFe/FeMn/NiFe multilayers

Abstract

The blocking effect of Mn diffusion in NiFe/(Mn,Cr)/FeMn/(Mn,Cr)/NiFe multilayer was investigated. The exchange biasing field ( H ex ) was maintained up to the inserted Mn thickness of 1.5 nm, while the H ex of the inserted Cr sample disappeared at 0.5 nm. To protect the interdiffusion of Mn atoms between FeMn and NiFe layers during the annealing process, an ultrathin Cr layer of 0.1 nm was inserted at the interfaces. The H ex of the 0.1 nm Cr sample was stabilized up to 400°C and the coercive field ( H c ) reduced to 40 percent.