Disordered iron germanium (FeGe) has recently garnered interest as a testbed for a variety of magnetic phenomena as well as for use in magnetic memory and logic applications. This is partially owing to its ability to host skyrmions and antiskyrmions -- nanoscale whirlpools of magnetic moments that could serve as information carriers in spintronic devices. In particular, a tunable skyrmion-antiskyrmion system may be created through precise control of the defect landscape in B20-phase FeGe, motivating developing methods to systematically tune disorder in this material and understand the ensuing structural properties. To this end, we investigate a route for modifying magnetic properties in FeGe. Specifically, we irradiate epitaxial B20-phase FeGe films with 2.8 MeV Au4+ ions, which creates a dispersion of amorphized regions that may preferentially host antiskyrmions at densities controlled by the irradiation fluence. To further tune the disorder landscape, we conduct a systematic electron diffraction study with in-situ annealing, demonstrating the ability to recrystallize controllable fractions of the material at temperatures ranging from approximately 150∘ C to 250∘C. Finally, we describe the crystallization kinetics using the Johnson-Mehl-Avrami-Kolmogorov model, finding that the growth of crystalline grains is consistent with diffusion-controlled one-to-two dimensional growth with a decreasing nucleation rate.
@article{arxiv.2409.02325,
title = {Structural Properties and Recrystallization Effects in Ion Beam Modified B20-type FeGe Films},
author = {Jiangteng Liu and Ryan Schoell and Xiyue S. Zhang and Hongbin Yang and M. B. Venuti and Hanjong Paik and David A. Muller and Tzu-Ming Lu and Khalid Hattar and Serena Eley},
journal= {arXiv preprint arXiv:2409.02325},
year = {2024}
}