{
  "abstract": "We give a closed-form construction of the $n$-qubit Elegant Joint Measurement (EJM) proposed in [PRL \\textbf{136}, 190201 (2026)] and show that it is part of a tunable family of measurements with tetrahedrally arranged Bloch vectors. The construction is based on the interference pattern implied by a single phase polynomial built from the elementary symmetric functions. It realises a regular tetrahedral measurement for every $n$, and the corresponding measurement unitary lies at level $n{+}1$ of the Clifford hierarchy. Starting from this measurement, we ask whether the size of the local tetrahedron -- and hence the entanglement of the basis -- can be varied while preserving its symmetry. For every even $n$ the answer is yes, and remarkably the size follows the same one-parameter law that governs the known two-qubit family, interpolating down to a $1$-uniform basis. For $n=3$ the EJM is locally isolated, while for odd $n\\ge5$ we do not know an analogous closed-form family. We also give an analogous construction, valid for every $n \\geq3$, with square local geometry.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: Phys. Rev. A 114, L050402 (2026)",
  "arxiv": "2607.16020",
  "author_total": 2,
  "authors": [
    {
      "name": "Jef Pauwels"
    },
    {
      "name": "Nicolas Gisin"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5pbg2jvs2atq0.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2607.16020",
  "fulltext_url": null,
  "id": "5pbg2jvs2atq0",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2607.16020",
  "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",
      "quant-ph"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2607.16020",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-03",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/5pbg2jvs2atq0.ris",
  "sources": [
    {
      "first_seen": "2026-11-04T15:21:24Z",
      "native_id": "2607.16020",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2607.16020"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Tunable Families of Multiqubit Elegant Joint Measurements",
  "title_text": "Tunable Families of Multiqubit Elegant Joint Measurements",
  "type": "preprint",
  "updated_at": "2026-11-06T18:21:01Z",
  "url": "https://research.draconitic.com/paper/5pbg2jvs2atq0",
  "venue": "arXiv",
  "versions": []
}