{
  "abstract": "Quantum infrared spectroscopy (QIRS), which exploits quantum interference between photon-pair generation processes, enables infrared spectroscopy using only visible and near-infrared (VNIR) light sources and detectors. Extending the spectral coverage of QIRS into the long-wavelength infrared region up to 20 {\\textmu}m is crucial for the identification and characterization of a broad range of materials. However, implementing QIRS beyond 10 {\\textmu}m has been challenging because the nonlinear materials used to date do not provide suitable photon-pair sources in this spectral region. Here, we design a wavelength-tunable photon-pair source based on a gallium selenide crystal and develop a QIRS system covering a broad spectral range from 8.6 to 20 {\\textmu}m. Using this system, we measure the transmittance spectrum of a polystyrene film and observe characteristic absorption bands beyond 10 {\\textmu}m relevant to identifying polystyrene and to probing local chain conformation. These results demonstrate that QIRS is capable of covering the entire molecular fingerprint region.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.00561",
  "author_total": 3,
  "authors": [
    {
      "name": "Yu Mukai"
    },
    {
      "name": "Ryo Okamoto"
    },
    {
      "name": "Shigeki Takeuchi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/533hpbrybwmy0.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.00561",
  "fulltext_url": null,
  "id": "533hpbrybwmy0",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.00561",
  "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"
    ],
    [
      "arxiv",
      "quant-ph"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.00561",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/533hpbrybwmy0.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T12:20:59Z",
      "native_id": "2611.00561",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.00561"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    },
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Ultra-broadband quantum infrared spectroscopy extending to 20 {\\textmu}m",
  "title_text": "Ultra-broadband quantum infrared spectroscopy extending to 20 {\\textmu}m",
  "type": "preprint",
  "updated_at": "2026-11-05T15:20:18Z",
  "url": "https://research.draconitic.com/paper/533hpbrybwmy0",
  "venue": "arXiv",
  "versions": []
}