Room-temperature side-gate-induced current modulation in a magnetic tunnel junction with an oxide-semiconductor barrier for vertical spin MOSFET operation

Realizing spin MOSFETs is essential for non-volatile high-speed electronics; however, obtaining practically large magnetoresistance (MR) is challenging because of the difficulties of growing high-quality single-crystalline ferromagnet/semiconductor heterostructures and of obtaining efficient gate modulation. In this study, for realizing a vertical spin MOSFET, we demonstrate side-gate-induced current modulation in a magnetic tunnel junction composed of Fe electrodes and an oxide semiconductor GaO x barrier at RT. We show gate modulation of the current up to ~10% and a MR ratio up to 40%, which is larger than that obtained at RT in previous spin-valve devices targeted for spin MOSFETs (~0.1%).