Room-temperature spin-orbit torque switching in a manganite-based heterostructure

The oxide ferromagnet La0.67Sr0.33MnO3 (LSMO) possesses low saturation magnetization (Ms), a low magnetic damping constant (??), and high carrier spin polarization, which promise superior functionalities in spintronics devices. For applications, these devices are to be integrated into electronic circuits, which require the control of the magnetization of LSMO by electrical means. However, a reliable electrical switching method remains largely unexplored. Here, we study the current-induced spin-orbit torque (SOT) in an all-oxide SrIrO3/LSMO bilayer. We found the magnetization of a 15 nm LSMO can be switched by electrical current, as confirmed from both the electrical transport measurement and the magnetic optical measurement. By taking advantage of the strain-mediated magnetic anisotropy, the magnetic easy axis of LSMO was controlled to be either perpendicular or parallel to the charge current direction such that a type-y or a type-x SOT switching was achieved, respectively. The dampinglike SOT efficiency is characterized to be 0.15 at room temperature according to the harmonic Hall voltage analysis. We also studied the temperature dependences of the SOT effective field and current-induced switching. Our demonstration of the electrical switching of LSMO magnetization at room temperature may stimulate SOT studies in a wide variety of all-oxide systems.