{
  "abstract": "Integrated nonlinear photonics demands waveguides that simultaneously offer ultra-low-loss, relatively strong nonlinearity, and tight mode confinement. Tantalum pentoxide (Ta2O5) is attractive for this purpose because it combines a broad transparency window, relatively strong third-order nonlinearity, and favorable thick-film growth characteristics. In tightly confined Ta2O5 waveguides, however, enhanced interaction between the optical mode and etched sidewalls makes scattering loss an important limitation for achieving high Q anomalous-dispersion resonators. Here, we mitigate this confinement-scattering trade-off in pure Ta2O5 waveguides using a fabrication flow based on the Damascene concept. The resulting microring resonators (MRRs) with a cross-section of 1.6 μm x 0.85 μm exhibit intrinsic quality factors exceeding 4.0 x 106, corresponding to propagation losses below 10 dB/m, while maintaining anomalous dispersion suitable for bright dissipative Kerr soliton operation. Using these resonators, we generate a coherent bright single-soliton microcomb with a repetition rate of 108.32 GHz. Under optimized dual-pump operating conditions, the platform further exhibits an experimentally accessible single-soliton window spanning 7.5 GHz, indicating a large detuning tolerance for soliton operation; this broad operating window is consistent with the relatively weak thermo-optic response of Ta2O5. Thermal-bistability analysis further indicates that the residual scattering loss is comparable to the material-absorption loss, rather than dominating the loss budget. These results demonstrate that low optical loss, tight mode confinement, and dispersion engineering suitable for soliton formation can be jointly achieved in a pure Ta2O5 platform, providing an ultra-low-loss platform foundation for integrated nonlinear photonic devices and more complex chip-scale nonlinear photonic systems.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: Optica 13, 2135-2143 (2026)",
  "arxiv": "2610.14878",
  "author_total": 11,
  "authors": [
    {
      "name": "Xiaotong Zhang"
    },
    {
      "name": "Shuxuan Guo"
    },
    {
      "name": "Ruixuan Yi"
    },
    {
      "name": "Zheze Shi"
    },
    {
      "name": "Like Shui"
    },
    {
      "name": "Long Huang"
    },
    {
      "name": "Leiran Wang"
    },
    {
      "name": "Yang Wang"
    },
    {
      "name": "Junling Qu"
    },
    {
      "name": "Wenfu Zhang"
    },
    {
      "name": "Xuetao Gan"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/73cm6zd2knyhf.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.14878",
  "fulltext_url": null,
  "id": "73cm6zd2knyhf",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.14878",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.optics"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2610.14878",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-10",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/73cm6zd2knyhf.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:06Z",
      "native_id": "2610.14878",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.14878"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "Ultra-low-loss Ta2O5 waveguide for integrated nonlinear photonics",
  "title_text": "Ultra-low-loss Ta2O5 waveguide for integrated nonlinear photonics",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:06Z",
  "url": "https://research.draconitic.com/paper/73cm6zd2knyhf",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1364/optica.607899",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}