{
  "abstract": "We present a theoretical framework for quantitative oxidation state mapping of transition-metal and rare-earth elements from near-atomic-resolution electron energy-loss spectroscopy (EELS) in complex oxide heterostructures. The total inelastic differential cross section of transition-metal L$_{2,3}$ and rare-earth M$_{4,5}$ edges is calculated by combining the relaxed Dirac-Hartree-Fock ionization cross section with ligand-field multiplet theory for the discrete transitions. We apply the approach to two correlated-oxide heterostructures, La$_{0.67}$Sr$_{0.33}$MnO$_3$/LaCr$_{0.2}$Mn$_{0.2}$Fe$_{0.2}$Co$_{0.2}$Ni$_{0.2}$O$_3$/SrTiO$_3$ and NdNiO$_3$/La$_{0.67}$Sr$_{0.33}$MnO$_3$/NdGaO$_3$, which include a wide range of transition-metal and rare-earth elements with overlapping features. The method resolves the oxidation states of Cr, Mn, Fe and Co and identifies the Ni contribution within the LaCr$_{0.2}$Mn$_{0.2}$Fe$_{0.2}$Co$_{0.2}$Ni$_{0.2}$O$_3$ layer at near-atomic resolution. We find predominantly Co$^{2+}$ together with mixed Mn$^{2+}$/Mn$^{3+}$/Mn$^{4+}$ character, indicating site-specific valence redistribution within the layer. We also separate overlapping spectral features, such as La-M$_{4,5}$ and Ni-L$_{2,3}$ edges in the NdNiO$_3$/La$_{0.67}$Sr$_{0.33}$MnO$_3$/NdGaO$_3$ heterostructure, thereby recovering the intrinsic Ni-L$_{2,3}$ excitation spectrum. We find that the effective Ni valence in NdNiO$_3$ deviates from the simple ionic picture. More broadly, this work establishes a generic method for quantitative valence mapping from near-atomic-resolution EELS, applicable to a wide range of experimental conditions for the study of local electronic structure of complex oxides.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.04797",
  "author_total": 6,
  "authors": [
    {
      "name": "Ioannis Iatrakis"
    },
    {
      "name": "Zitao Zhang"
    },
    {
      "name": "Ricardo Egoavil"
    },
    {
      "name": "Emma van der Minne"
    },
    {
      "name": "Christoph Baeumer"
    },
    {
      "name": "Frank de Groot"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fazb5mebat35w.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.04797",
  "fulltext_url": null,
  "id": "fazb5mebat35w",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.04797",
  "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",
      "physics.atom-ph"
    ],
    [
      "openalex",
      "2508|Electron and X-Ray Spectroscopy Techniques"
    ]
  ],
  "openalex": "W7220741688",
  "pdf_url": "https://arxiv.org/pdf/2610.04797",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-03",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/fazb5mebat35w.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:01Z",
      "native_id": "2610.04797",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.04797"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.atom-ph",
      "subfield": "amo"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Quantitative near-atomic-resolution oxidation-state mapping in complex oxide heterostructures by electron energy-loss spectroscopy",
  "title_text": "Quantitative near-atomic-resolution oxidation-state mapping in complex oxide heterostructures by electron energy-loss spectroscopy",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:01Z",
  "url": "https://research.draconitic.com/paper/fazb5mebat35w",
  "venue": "arXiv",
  "versions": []
}