Highly Energy-Efficient Spin Current Generation in SrIrO₃ by Manipulating the Octahedral Rotation

Materials with strong spin–orbit coupling (SOC) have been continuously attracting intensive attention due to their promising application in energy-efficient, high-density, and nonvolatile spintronic devices. Particularly, transition-metal perovskite oxides with strong SOC have been demonstrated to exhibit efficient charge–spin interconversion. In this study, we systematically investigated the impact of epitaxial strain on the spin–orbit torque (SOT) efficiency in the SrIrO 3 (SIO)/Ni 81 Fe 19 (Py) bilayer. The results reveal that the SOT efficiency is strongly related to the octahedral rotation around the in-plane axes of the single-crystal SIO. By modulating the epitaxial strain using different substrates, the SOT efficiency can be remarkably improved from 0.15 to 1.45. This 10-fold enhancement of SOT efficiency suggests that modulating the epitaxial strain is an efficient approach to control the SOT efficiency in complex oxide-based heterostructures. Our work may have the potential to advance the application of complex oxides in energy-efficient spintronic devices.