Tuning the High‐Efficiency Field‐Free Current‐Induced Deterministic Switching via Ultrathin PtMo Layer with Mo Content
Zelalem Abebe Bekele, Runze Li, Yucai Li, Yi Cao, Xionghua Liu, Kaiyou Wang
Abstract
Abstract Spin‐orbit torque (SOT)‐based magnetization switching is a promising candidate for the innovation and developments of spintronic devices. However, the necessity of an in‐plane magnetic field to induce deterministic switching is an obstacle to feasibility in practical applications. Here, it is shown that the field‐free current‐induced magnetization switching in a perpendicular magnetized Pt 1− x Mo x /Co/Ru heterostructure with x = 0, 0.04, 0.07, 0.12, and 0.17. Applying an in‐plane charge current through the Pt 1− x Mo x layer, the device can achieve a high‐efficiency field‐free current‐induced magnetization switching with competing spin currents generated from a single Pt 1− x Mo x alloy layer due to opposite spin Hall angles (θ SHA ) of Pt and Mo atoms and locally induced electric field. Remarkably, the large θ SHA of about 0.35 is achieved in the optimal composition of Pt 0.88 Mo 0.12 alloy, which is much higher than that of the pure Pt structure. The results pave the way to resolve the future problems of scalability and thermal stability for SOT‐driven magnetic tunnelling junctions.