{
  "abstract": "Optical cycling refers to repeated excitation and spontaneous emission on an electronic transition in an atom or molecule. Optical cycling in molecules can enable a wide range of quantum control and readout techniques, but unfortunately it has only been demonstrated on a small class of alkali-like or alkaline-earth-like molecules. Thorium monoxide (ThO), a molecule used in one of the most precise permanent electron electric dipole moment (eEDM) searches (ACME [1]), does not fall into this category. In this work, we demonstrate the first optical cycling on this non-conventional class over a range of experimental parameter space, including laser intensity, polarization switching rate, and interaction time. We show that both the $J = 1, 2$ rotational levels of ThO molecule are capable of cycling $11(2)$ photons on average with a single laser, at $1.9(6) \\times 10^{6}~\\mathrm{s}^{-1}$ and $2.3(7)\\times 10^6~\\mathrm{s}^{-1}$ scattering rate, respectively, before population is lost to other vibronic levels. We outline a scheme to apply this demonstrated optical cycling in an ACME-style eEDM measurement, improving the detection efficiency by over fourfold compared to non-cycling fluorescence detection. This would lead to over a twofold enhancement in the statistical sensitivity of the eEDM search. This optical cycling scheme can be further extended to scatter about 100 photons, which would enable a wider range of quantum control and sensing using ThO molecules. [1] V. Andreev, D. G. Ang, D. DeMille, J. M. Doyle, G. Gabrielse, J. Haefner, N. R. Hutzler, Z. Lasner, C. Meisenhelder, B. R. O`Leary, C. D. Panda, A. D. West, E. P. West, and X. Wu, Nature 562, 355 (2018).",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2605.28509",
  "author_total": 6,
  "authors": [
    {
      "name": "Alexander Frenett"
    },
    {
      "name": "Dorothy Gan"
    },
    {
      "name": "Nicholas Emtage"
    },
    {
      "name": "Monika Fouad"
    },
    {
      "name": "Sebastian Miki-Silva"
    },
    {
      "name": "Xing Wu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/e4x9khgt55set.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2605.28509",
  "fulltext_url": null,
  "id": "e4x9khgt55set",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2605.28509",
  "language": null,
  "licence": "CC-BY-NC-SA-4.0",
  "licence_label": "CC BY-NC-SA 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by-nc-sa/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.atom-ph"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2605.28509",
  "pmcid": null,
  "pmid": null,
  "published": "2026-06-08",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/e4x9khgt55set.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:48Z",
      "native_id": "2605.28509",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2605.28509"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.atom-ph",
      "subfield": "amo"
    }
  ],
  "title": "Optical cycling on thorium monoxide (ThO) for an improved test of fundamental symmetries",
  "title_text": "Optical cycling on thorium monoxide (ThO) for an improved test of fundamental symmetries",
  "type": "preprint",
  "updated_at": "2026-10-30T12:19:48Z",
  "url": "https://research.draconitic.com/paper/e4x9khgt55set",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1103/wzf3-7h5g",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}