{
  "abstract": "The ferromagnetic nitride Fe$_{4}$N has attracted attention for application in spintronic devices due to its high spin polarization and large magnetostriction. We present a combined experimental and theoretical study on the magnetostriction of Fe$_{4-x}$Co$_{x}$N films across a wide composition range. The Fe$_{4-x}$Co$_{x}$N films were grown on SrTiO$_{3}$(001) substrates using molecular beam epitaxy, and the magnetostriction constants along the [100] direction ($λ$$_{100}$) and [111] direction ($λ$$_{111}$) were precisely evaluated using an optical cantilever method. The experimental results reveal that $λ$$_{111}$ remains positive in the whole composition range and shows a maximum value of +82 ppm around x = 0.9. The variation in $λ$$_{111}$ with x is much smaller than that in $λ$$_{100}$, for which giant tunability and sign reversal are observed. First-principles calculations show reasonable agreement with the experimental $λ$$_{111}$ for x ${\\ge}$ 1.6, but give negative values at lower x, and an exceptionally large negative $λ$$_{111}$ is obtained at x = 0.8, where the Fermi level coincides with a pronounced minority-spin peak in the density of states. The calculated $λ$$_{111}$ depends strongly on the smearing parameter, indicating that the rhombohedral magnetostriction is highly sensitive to the treatment of atomic disorder. The saturation magnetostriction constant ($λ$$_{s}$) derived from $λ$$_{100}$ and $λ$$_{111}$ is also compared with the $λ$$_{s}$ measured for the (001)-oriented polycrystalline Fe$_{4-x}$Co$_{x}$N films, and a possible scenario for deviation between them is discussed. Our findings clarify the basic features of magnetostriction in the Fe$_{4-x}$Co$_{x}$N system, providing essential magnetoelastic parameters for designing nitride-based spintronic devices.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.28864",
  "author_total": 7,
  "authors": [
    {
      "name": "Huameng Yu"
    },
    {
      "name": "Keita Ito"
    },
    {
      "name": "Shoya Sakamoto"
    },
    {
      "name": "Ivan Kurniawan"
    },
    {
      "name": "Yoshio Miura"
    },
    {
      "name": "Yasushi Endo"
    },
    {
      "name": "Takeshi Seki"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/db1433tr90ned.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.28864",
  "fulltext_url": null,
  "id": "db1433tr90ned",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.28864",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "openalex",
      "3107|Magnetic properties of thin films"
    ]
  ],
  "openalex": "W7214359441",
  "pdf_url": "https://arxiv.org/pdf/2609.28864",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-24",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/db1433tr90ned.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:24:11Z",
      "native_id": "2609.28864",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.28864"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Magnetostrictive properties in Fe$_{4-x}$Co$_{x}$N films: Insight from experiments and first-principles calculations",
  "title_text": "Magnetostrictive properties in Fe_4−xCo_xN films: Insight from experiments and first-principles calculations",
  "type": "preprint",
  "updated_at": "2026-10-30T12:24:11Z",
  "url": "https://research.draconitic.com/paper/db1433tr90ned",
  "venue": "arXiv",
  "versions": []
}