Co/Pt multilayer-based pseudo spin valves with perpendicular magnetic anisotropy

摘要: Pseudo spin valves (SVs) exhibiting perpendicular magnetic anisotropy were prepared by magnetron sputtering. Magnetization measurements of the Co/Pt multilayers performed to select reference and free layers. The selection criteria are square hysteresis loops, weaker current shunting effect, proper coercivity. optimal layer Pt(5.0 nm)/[Co(0.4 nm)/Pt(0.6 nm)]3/Co(0.4 nm)/Cu(3.0 nm) Cu(3.0 nm)/[Co(0.4 nm)/Pt(1.5 nm)]4, respectively. resulting pseudo SV exhibits two well-separated loops when field is applied film plane. minor loop corresponding shifts toward negative direction axis, indicating ferromagnetic interlayer exchange coupling between also enhances coercivity (H C) both giant magnetoresistance (GMR) 2.7 % achieved with in plane measurement. GMR first increases Pt seed thickened, reaches a maximum 3.0 % at 4 nm then decreases further increase thickness. But thicker Cu spacer always lowers SV.