Magnetoresistance of [Ni(Pt)/Mn] Superlattice-Based Spin Valves

The magnetoresistance (MR) of [Ni/Mn] superlattice-based spin valves was compared with that of [Pt/Mn] superlattice. The [Ni/Mn] superlattice after a thermal treatment at 240 °C showed a fct (face centered tetragonal) structure with an antiferromagnetic phase. The thermal stability of its spin valves increased gradually with the annealing treatment. As-deposited [Pt/Mn] superlattice-based spin valves showed an exchange coupling field (H_ex) of 17 Oe and an MR ratio of 1.2% without deposition field. The surface morphologies of the two superlattice-based spin valves were dominantly different after annealing.