Giant enhancement of spin accumulation and long-distance spin precession in metallic lateral spin valves

金属面内スピンバルブにおけるスピン蓄積の巨大増幅と長距離スピン制御

福間 康裕*; Le, W.*; 井土 宏*; 高橋 三郎; 前川 禎通; 大谷 義近*

Fukuma, Yasuhiro*; Le, W.*; Izuchi, Hiroshi*; Takahashi, Saburo; Maekawa, Sadamichi; Otani, Yoshichika*

The non-local spin injection in lateral spin valves is strongly expected to be an effective method to generate a pure spin current for potential spintronic application. However, the spin-valve voltage, which determines the magnitude of the spin current flowing into an additional ferromagnetic wire, is typically of the order of 1V. Here we show that lateral spin valves with low-resistivity NiFe/MgO/Ag junctions enable efficient spin injection with high applied current density, which leads to the spin-valve voltage increasing 100-fold. Hanle effect measurements demonstrate a long-distance collective 2 spin precession along a 6-m-long Ag wire. These results suggest a route to faster and manipulable spin transport for the development of pure spin-current-based memory, logic and sensing devices.