All-electric spin transistor using perpendicular spins

All-electric spin transistor is demonstrated using perpendicular spins in an InAs quantum well channel. For the injection and detection of perpendicular spins in the quantum well channel, we use Tb₂₀Fe₆₂Co₁₈/Co₄₀Fe₄₀B₂₀ electrodes, where the Tb₂₀Fe₆₂Co₁₈ layer produces the perpendicular magnetization and the Co₄₀Fe₄₀B₂₀ layer enhances the spin polarization. In this spin transistor device, a gate-controlled spin signal as large as 80 mΩ is observed at 10 K without an external magnetic field. In order to confirm the spin injection and relaxation independently, we measure the three-terminal Hanle effect with an in-plane magnetic field, and obtain a spin signal of 1.7 mΩ at 10 K. These results clearly present that the electric field is an efficient way to modulate spin orientation in a strong spin-orbit interaction system.