Observation of Topological Hall Effect in Synthetic Antiferromagnetic Skyrmion System

Synthetic antiferromagnetic skyrmions have emerged as promising candidates for next-generation high-speed and highly integrated spintronic devices, owing to their exceptional properties such as high driving velocity, nanoscale dimensions, and the absence of the skyrmion Hall effect. In this work, we report the experimental observation of the topological Hall effect in both compensated and non-compensated synthetic antiferromagnetic skyrmion systems based on [Pt/Co/Ru]2 trilayer. The antiferromagnetic skyrmions are further demonstrated to be robust in these synthetic antiferromagnets under zero-field. Our first-principles calculations and transmission electron microscope measurements show that the observed topological Hall Effect is related to the skyrmion structures in the Ru and Pt layers induced by the magnetic proximity effect and atomic diffusion. This work examines the role of the magnetic proximity effect in the topological Hall effect of SAF skyrmions in these systems.