Generation and Detection of Out‐of‐Plane‐Polarized Spin Current in a Lateral Spin Valve with Amorphous Multilayer Electrodes

Spin injection and detection in a lateral spin valve, through perpendicularly magnetized electrodes made from an amorphous ferromagnetic [CoSiB/Pt]_N=7 multilayer film, are investigated. The out‐of‐plane‐polarized spin current in a diffusive metallic copper produces a signal that switches with the relative directions of the injecting and the detecting electrode's magnetization. The magnitude of the switching signal corresponds to 533 μΩ at 80 K and increases to 625 μΩ at 30 K. These values are about ten times and 100 times larger than those observed with [Co/Ni] and [Co/Pd] perpendicular magnetic multilayer electrodes, respectively. It is further confirmed that the obtained spin signal under the application of in‐plane magnetic field decreases due to Hanle precession. The extracted spin relaxation time (τ_s) and spin diffusion length (λ_s) from the Hanle fitted curve are 10.2 ps and 311 nm, respectively.