{
  "abstract": "Quasi-two-dimensional (2D) van der Waals (vdW) ferromagnets such as the series Fe$_{3-x}$GeTe$_2$, with a relatively high Curie temperature and robust metallicity, offer an ideal platform for investigating itinerant magnetism in reduced dimensions. Here, we present a comprehensive electron spin resonance (ESR) investigation of single-crystalline almost-stoichiometric Fe$_{3.03 \\pm 0.03}$GeTe$_{2}$ across wide ranges of frequencies, temperatures, and magnetic fields to gain quantitative insights into its magnetic anisotropy and spin dynamics. Frequency-dependent ESR measurements establish Fe$_{3}$GeTe$_{2}$ as an easy-axis ferromagnet. Temperature-dependent high-field ESR reveals a large internal field that gradually decreases at higher temperatures. Remarkably, this internal field persists even above $T_\\mathrm{C}$, evidencing short-range spin correlations in Fe$_{3}$GeTe$_{2}$. Analysis of spin-wave modes yields a strong uniaxial magnetocrystalline anisotropy $K_{\\text{int}} \\approx - 5 \\times 10^6$ erg cm$^{-3}$ at 3 K and a large magnon gap $Δ(3 \\mathrm{K})$ $\\approx$ 87.8 $\\pm$ 13.7 GHz ($\\approx$ 0.363 $\\pm$ 0.057 meV). Our study highlights that small variations in Fe content in Fe$_{3}$GeTe$_{2}$ lead to substantial changes in the magnon gap at low temperatures, indicating the extreme sensitivity of spin dynamics to the chemical composition. These results establish Fe$_{3}$GeTe$_{2}$ as a model vdW ferromagnet for exploring tunable anisotropies and magnon excitations in metallic 2D magnets.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: Physical Review B, 2026",
  "arxiv": "2607.24543",
  "author_total": 8,
  "authors": [
    {
      "name": "Riju Pal"
    },
    {
      "name": "Joyal John Abraham"
    },
    {
      "name": "Satyabrata Bera"
    },
    {
      "name": "Mintu Mondal"
    },
    {
      "name": "Atindra Nath Pal"
    },
    {
      "name": "Bernd Buchner"
    },
    {
      "name": "Vladislav Kataev"
    },
    {
      "name": "Alexey Alfonsov"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/brssszvre23t8.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2607.24543",
  "fulltext_url": null,
  "id": "brssszvre23t8",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2607.24543",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "arxiv",
      "cond-mat.str-el"
    ],
    [
      "openalex",
      "3104|Advanced Condensed Matter Physics"
    ]
  ],
  "openalex": "W7171564838",
  "pdf_url": "https://arxiv.org/pdf/2607.24543",
  "pmcid": null,
  "pmid": null,
  "published": "2026-07-27",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/brssszvre23t8.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:36:28Z",
      "native_id": "2607.24543",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2607.24543"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Magnetic anisotropy in the near-stoichiometric van der Waals ferromagnet Fe$_3$GeTe$_2$",
  "title_text": "Magnetic anisotropy in the near-stoichiometric van der Waals ferromagnet Fe_3GeTe_2",
  "type": "preprint",
  "updated_at": "2026-11-01T12:20:47Z",
  "url": "https://research.draconitic.com/paper/brssszvre23t8",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1103/27h2-qnt8",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}