Magnetic Structure of Domain Walls Confined in a Nano-Oxide Layer

In the recent years, a spin valve was developed with a current-confined-path structure consisting of a non-oxide-layer. We analyze magnetic structures of the current-confined-path in the nano-oxide layer sandwiched between ferromagnetic electrodes and clarify the dependency of the magnetic structure on the shape and size of the current-confined path. Our results of stiffness energy density and thermal stability shows that we should fabricate a current perpendicular to the plane spin valve with narrow current-confined paths with a large aspect ratio and strong constriction in order to enhance the magnetoresistance ratio.