{
  "abstract": "Sagnac interferometers are important tools for precision measurements. Cancellation of common-path noise ensures a high degree of stability against external perturbations, while their sensitivity to rotations provides the basis of laser gyroscopes. Here we highlight another, less explored feature of Sagnac interferometers: the fact that optical elements are traversed in reverse order for clockwise and counterclockwise propagating light components. This provides the opportunity to explore a classical realization of indefinite causal order, where the order of events within a sequence is not fixed. We explore this concept to identify the geometric phase associated with two non-commuting polarization operations with a single measurement. This idea may have applications for the rapid determination of polarization manipulations or optical activity within chiral media, but foremost it provides a geometric illustration of indefinite causal order.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.01540",
  "author_total": 7,
  "authors": [
    {
      "name": "Lucas Marques Fagundes"
    },
    {
      "name": "Finlay Campbell"
    },
    {
      "name": "Richard Aguiar Maduro"
    },
    {
      "name": "Renné Medeiros de Araújo"
    },
    {
      "name": "Stephen M. Barnett"
    },
    {
      "name": "Sarah Croke"
    },
    {
      "name": "Sonja Franke-Arnold"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1x9n6gyvvyhyx.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.01540",
  "fulltext_url": null,
  "id": "1x9n6gyvvyhyx",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.01540",
  "language": null,
  "licence": "CC-BY-SA-4.0",
  "licence_label": "CC BY-SA 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by-sa/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.optics"
    ],
    [
      "openalex",
      "3107|Quantum Mechanics and Applications"
    ]
  ],
  "openalex": "W7215904678",
  "pdf_url": "https://arxiv.org/pdf/2610.01540",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/1x9n6gyvvyhyx.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:26:03Z",
      "native_id": "2610.01540",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.01540"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "Measuring Geometric Phase based on Indefinite Causal Order in a Sagnac Interferometer",
  "title_text": "Measuring Geometric Phase based on Indefinite Causal Order in a Sagnac Interferometer",
  "type": "preprint",
  "updated_at": "2026-10-30T12:26:03Z",
  "url": "https://research.draconitic.com/paper/1x9n6gyvvyhyx",
  "venue": "arXiv",
  "versions": []
}