Composition and temperature dependent magnetic transport and magnetization switching in W/Tb1−xCox/W multilayer films

With the increasing demand for higher storage speed and density in information technology, spin–orbit torque (SOT)-based magnetic random access memory has attracted considerable attention because of its fast read/write operation and high endurance. Rare-earth-transition-metal ferrimagnetic alloys exhibit strong bulk perpendicular magnetic anisotropy and tunable magnetic compensation, which make them promising candidates for high-density and thermally stable SOT devices. In this work, a series of perpendicularly magnetized W/Tb1−xCox/W heterostructure films were fabricated by direct current magnetron co-sputtering. The effects of composition on the magnetic properties, together with the temperature-dependent evolution of the Tb and Co sublattice moments, were systematically investigated. The results reveal a clear composition compensation point at room temperature, where the coercivity shows a pronounced enhancement. Variable-temperature measurements further identify a composition-dependent temperature compensation point (Tcomp), confirming the distinct thermal responses of the two sublattices. In addition, deterministic current-driven magnetization switching was achieved under an in-plane assist field. These findings provide an experiment for optimizing ferrimagnetic SOT devices over a wide temperature range.