Exchange bias characteristic in [Co/Pd]n/FEMN bi-layered thin films with perpendicular anisotropy and the applications for spin-valves in spintronics

Abstract

A detailed insight into the physical origin of the perpendicular exchange bias (PEB), as well as effective solutions to improve PEB characteristics has been studied in this work. A physical model of PEB based on the total energy equation per unit area of an exchange bias system is established and experimentally confirmed. The model proposes that PEB is a result of the energy competition between the anisotropy energies, KAFM?tAFM, KFM,eff?tFM, and the interfacial coupling energy, Jex. The seed layer effects as well as the magnetoelastic effect have also been studied to improve PEB characteristics experimentally. Finally, a PEB GMR spin valve device with a high magnetic and thermal stability as well as high GMR performance is developed by implementing the theoretical and experimental results obtained from PEB bi-layered thin films