Benchmarking interfacial magnetic interactions and spin Hall angle in heavy metal /CoFeB/MgO heterostructures

Abstract

The stability and efficient electrical control of chiral spin textures (CSTs) is critical for their implementation in racetrack device architectures. Three principal properties determine the utility of material platforms for spin-texture dynamics: perpendicular magnetic anisotropy (PMA), Dzyaloshinskii–Moriya interaction (DMI), and spin Hall angle (SHA). Notwithstanding individual studies, a comprehensive benchmarking of these key interactions across racetrack-compatible material systems remains lacking. Here, we systematically evaluate tunnel-readout compatible HM/CoFeB/MgO trilayers fabricated using wafer-scale techniques. Their key properties—PMA, DMI, and SHA—were characterized across four heavy metals (Pt, W, Ta, and Ir) and two CoFeB compositions using magnetometry, spectroscopy, and transport techniques, respectively. Our results reveal that the W-based stacks exhibit robust PMA and high SHA, while the Pt-based stacks provide the strongest DMI. Notably, both DMI and SHA depend strongly on both heavy metal and CoFeB composition, underscoring the critical role of alloy engineering in controlling interfacial magnetic properties. Our work provides quantitative benchmarks and materials design principles for developing next-generation CST-based racetrack devices.