The current-driven motion of magnetic domain walls (DWs) is the working principle of magnetic racetrack memories. In this type of spintronic technology, high current densities are used to propel DW motion in magnetic nanowires, causing significant wire heating. Synthetic antiferromagnets are known to show very fast DW motion at high current densities, but lower current densities around onset of motion have received less attention. Here we use scanning transmission x-ray microscopy to study the response of DWs in a SAF multilayer to currents. We observe that the DWs depin at ∼3×1011~A/m2 and move more quickly in response to 5~ns duration current pulses than in comparable conventional multilayers. The results suggest that DWs in SAF structures are superior to conventional N\'{e}el DWs for low energy consumption racetrack technologies.
@article{arxiv.2205.03126,
title = {Domain wall motion at low current density in a synthetic antiferromagnet nanowire},
author = {Christopher Barker and Simone Finizio and Eloi Haltz and Sina Mayr and Philippa Shepley and Thomas Moore and Gavin Burnell and Jörg Raabe and Christopher Marrows},
journal= {arXiv preprint arXiv:2205.03126},
year = {2023}
}