  In the recent years, a spin-valve was developed with a current-confined-path
structure consisting of a non-oxide-layer (NOL). We analyze magnetic structures
of the current-confinedpath 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 CPP
spin-valve with narrow current-confinedpaths with large aspect ratio and strong
constriction in order to enhance the MR ratio.
