The spin-dependent CPP (current perpendicular to plane) transport properties in semiconductive-oxide(MOx)/ferromagnet multilayers consisting of CoPt/Co/MOx/Co/MOx/Co/CoPt, where M = Ti, Sn, were investigated by magneto-transport measurement. The XRD patterns reveal that the structures of sputtered MOx films are amorphous or nanocrystalline. The MR ratio of a TiOx-based multilayer (0.43%) was much smaller than that of a SnOx-based one (2.0%) at T = 77 K. As inferred from the shape of MR curves with a large saturation field above 4kOe, suppressed MR change in the TiOx-based multilayer is caused by the interlayer diffusion of Co atoms into the TiOx layer. The same behavior was not observed in the SnOx-based one. The MR ratio was reduced by half on increasing tSnO(x) from 4 to 8 nm. This decrease can be ascribed to the scattering of the spin-polarized electron in the SnOx layer.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics