All-electric spin transistor using perpendicular spins

• We realize all-electric spin-FET using perpendicular spins.
• Gate modulation of spin orientation is detected in a quantum well layer.
• A gate-controlled spin signal as large as 80 mΩ is obtained at 10 K.
• We compare spin injection signals driven by a magnetic field and an electric field.

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.