{
  "abstract": "Microresonators based on diverse material platforms have driven the progress of integrated photonics by enhancing light-matter interactions in compact volumes. Extending this strategy to magneto-optical (MO) media is highly attractive for nonreciprocal photonics, magnonics, and quantum transduction, yet compact high-Q resonators based on single-crystalline yttrium iron garnet (YIG) have remained elusive because of the difficulty of its nanofabrication. Here we demonstrate high-Q, small-mode-volume MO microdisk resonators based on monocrystalline Bi-substituted YIG (Bi:YIG). Low-loss Bi:YIG thin films prepared by bonding and thinning, combined with optimized Ar-plasma etching, enable submicron-thick, air-suspended microdisks that support telecom-band whispering-gallery modes with $Q = 1.52\\times 10^5$, a mode volume $V \\approx 200$ cubic wavelengths, and $Q/V \\approx 760$, representing an orders-of-magnitude improvement for integrated high-Q YIG MO cavities. The device exhibits clear magnetic-field-dependent spectral responses, including reciprocal resonance shifts and nonreciprocal frequency splitting of counter-propagating modes. A perturbative analytical model quantitatively reproduces these responses and indicates an effective MO coefficient about twice the bulk value, suggesting a possible miniaturization-induced enhancement. These results establish monocrystalline YIG microdisks as a compact high-Q MO platform for integrated isolators, optomechanics, microcombs, and photon-magnon quantum interfaces.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.22841",
  "author_total": 10,
  "authors": [
    {
      "name": "Takeru Yambe"
    },
    {
      "name": "Kota Taniguchi"
    },
    {
      "name": "Tatsuya Kitai"
    },
    {
      "name": "Daisuke Sato"
    },
    {
      "name": "Syuan Gao"
    },
    {
      "name": "Hajime Kumazaki"
    },
    {
      "name": "Shun Fujii"
    },
    {
      "name": "Takasumi Tanabe"
    },
    {
      "name": "Satoshi Iwamoto"
    },
    {
      "name": "Yasutomo Ota"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2frzphqf59c3j.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.22841",
  "fulltext_url": null,
  "id": "2frzphqf59c3j",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.22841",
  "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",
      "physics.optics"
    ],
    [
      "openalex",
      "2208|Magneto-Optical Properties and Applications"
    ]
  ],
  "openalex": "W7214050670",
  "pdf_url": "https://arxiv.org/pdf/2609.22841",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-19",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2frzphqf59c3j.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:19Z",
      "native_id": "2609.22841",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.22841"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "High-Q Magneto-Optical Microdisk Resonators Based on Monocrystalline Bismuth-substituted Yttrium Iron Garnets",
  "title_text": "High-Q Magneto-Optical Microdisk Resonators Based on Monocrystalline Bismuth-substituted Yttrium Iron Garnets",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:19Z",
  "url": "https://research.draconitic.com/paper/2frzphqf59c3j",
  "venue": "arXiv",
  "versions": []
}