Ultralarge Spin Hall Angle via TiO2 Nanocluster-Mediated Side-Jump Scattering.

Spin-orbit torque (SOT) enables efficient magnetization switching via the spin Hall effect in heavy metals, yet existing materials face tradeoffs between spin Hall angle, conductivity, and process compatibility. Here, W1- x(TiO2)x nanocomposites are reported by incorporating TiO2 nanoclusters into the β-phase W, achieving a maximum spin Hall angle of -1.66 and damping-like SOT efficiency of -0.94, representing 114% enhancement over pure W. By theoretically separating the contributions of the intrinsic and extrinsic mechanisms of the spin Hall effect, the enhancement of spin-orbit torque efficiency originates from substantial side jump induced by TiO2 nanoclusters. Current-induced magnetization switching of W0.88(TiO2)0.12 demonstrates ultralow critical density (1.78 × 106 A cm-2). Combined with its cost-effectiveness and low power consumption, these results position W0.88(TiO2)0.12 as a promising candidate to replace conventional β-W in industrial SOT-magnetic random-access memory applications.