A wide variety of chiral non-collinear spin textures have been discovered and have unique properties that make them highly interesting for technological applications. However, many of these are found in complex materials and only in a narrow window of temperature. Here, we show the formation of Neel-type skyrmions in thin layers of simple ferromagnetic alloys, namely Co-Al and Co-Ni-Al, over a wide range of temperature up to 770 K, by imposing a vertical strain gradient via epitaxy with an Ir-Al underlayer. The Neel skyrmions are directly observed using Lorentz transmission electron microscopy in freestanding membranes at high temperatures and the strain gradient is directly measured from x-ray diffraction anomalous peak profiles. Our concept allows simple centrosymmetric ferromagnets with high magnetic ordering temperatures to exhibit hot skyrmions, thereby, bringing closer skyrmionic electronics.
@article{arxiv.2510.06488,
title = {High temperature Neel skyrmions in simple ferromagnets},
author = {Peng Wang and Rana Saha and Holger L. Meyerheim and Ke Gu and Hakan Deniz and David Eilmsteiner and Andrea Migliorini and Juan Rubio Zuazo and Engenia Sebastiani-Tofano and Ilya Kostanovski and Abhay Kant Srivastava and Arthur Ernst and Stuart S. P. Parkin},
journal= {arXiv preprint arXiv:2510.06488},
year = {2025}
}
Comments
Main manuscript 21 pages, 5 figures, this is initial submission version, revised version is under review. This work is an extension from Peng Wang's PhD thesis