Phase‐Transition‐Controlled Modulation of Spin–Orbit Torques in VO ₂ ‐Based Heterostructures by Orbital Hall Effect

ABSTRACT Spin–orbit torques (SOTs) have emerged as one of the promising means to manipulate the magnetization switching, where tunable and enhanced SOT efficiencies are desirable for functional applications. Vanadium dioxide (VO 2 ), as a strongly correlated oxide with a metal‐insulator transition (MIT) behavior near room temperature, presents an intriguing yet under‐explored platform for SOT modulation. Here, current‐induced spin–orbit torques in VO 2 /Pt/Co/Pt heterostructures are investigated using the second‐harmonic Hall voltage measurements across VO 2 ’s MIT temperature, and a nearly 300% abrupt variation in SOT efficiency is revealed. We experimentally demonstrate that this dramatic modulation originates from the sudden increase of orbital currents in VO 2 metallic phase, which markedly enhances the damping‐like SOT efficiency to 0.45 at room temperature—near five times that of archetypal Pt/Co/Pt. Consequently, the critical switching current density decreases to 5.73 × 10 6 A cm −2 , accompanied by a 60% reduction in the total device power consumption. This work displays a strong tunability of SOT efficiency, highlighting the potential of VO 2 for energy‐efficient, thermally programmable memory and logic devices, and paves the way for spin‐orbitronics based on strongly correlated oxides.