{
  "abstract": "Finite-size effects are ubiquitous in quantum matter, yet typically invisible in the thermodynamic limit; when system size is restricted, boundaries and confinement reveal modified spectra, correlations, and emergent phenomena. With growing access to well-controlled few-spin systems, these effects are now directly observable and offer a route to probing universal physics and enabling quantum information applications. Here, we study finite-size physics in the quasi-one-dimensional Ising-like quantum antiferromagnet Ba(Co$_{1-x}$Mg$_x$)$_2$V$_2$O$_8$ with $x = 2\\%$ and $x = 5\\%$, where non-magnetic Mg$^{2+}$ ions fragment the Co$^{2+}$ spin chains into finite segments. Combining inelastic neutron scattering and numerical calculations, we identify distinct regimes with fundamentally different low-energy quantum excitations: spinons confined to chain boundaries, and a cluster mode in shorter chains corresponding to a collective reversal of the Néel-ordered segment without classical analogue. Our results demonstrate how chemical substitution acts as a quantum microscope providing direct access to boundary-shaped excitations in strongly correlated spin systems.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.34596",
  "author_total": 10,
  "authors": [
    {
      "name": "Quentin Faure"
    },
    {
      "name": "Shintaro Takayoshi"
    },
    {
      "name": "Virginie Simonet"
    },
    {
      "name": "Béatrice Grenier"
    },
    {
      "name": "Stéphane Raymond"
    },
    {
      "name": "Eric Ressouche"
    },
    {
      "name": "Xavier Fabrèges"
    },
    {
      "name": "Pascal Lejay"
    },
    {
      "name": "Thierry Giamarchi"
    },
    {
      "name": "Sylvain Petit"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/edpz7hyz4pw35.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.34596",
  "fulltext_url": null,
  "id": "edpz7hyz4pw35",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.34596",
  "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"
    ],
    [
      "arxiv",
      "cond-mat.str-el"
    ],
    [
      "openalex",
      "3104|Advanced Condensed Matter Physics"
    ]
  ],
  "openalex": "W7223784453",
  "pdf_url": "https://arxiv.org/pdf/2610.34596",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-25",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/edpz7hyz4pw35.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:35Z",
      "native_id": "2610.34596",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.34596"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Non-magnetic impurities as a quantum microscope of finite size effects in spin chains",
  "title_text": "Non-magnetic impurities as a quantum microscope of finite size effects in spin chains",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:35Z",
  "url": "https://research.draconitic.com/paper/edpz7hyz4pw35",
  "venue": "arXiv",
  "versions": []
}