{
  "abstract": "We experimentally demonstrate second- and third-order exceptional bound states in the continuum (EP-BICs), formed by the merging of two and three symmetry-protected BICs at an exceptional point (EP). Our passive reciprocal acoustic platform consists of symmetry-protected BIC cavities coupled through an acoustic waveguide and enables independent control of intrinsic loss, radiative loss, and near-field coupling between the cavities. A nonuniformly distributed intrinsic loss provides the non-Hermiticity required for EP formation while preserving decoupling from the waveguide radiation channel. The EP-BICs are probed using both near- and far-field excitation. In the near field, local intracavity excitation directly accesses the symmetry-protected BICs and reveals their spectral evolution. For far-field excitation, we intentionally break the protecting geometrical symmetry, converting the BICs into quasi-BICs and making them accessible through transmission measurements. Extending the system to three cavities with graded intrinsic loss realizes a third-order EP-BIC and yields a larger spectral response to the implemented coupling perturbation. These results establish a passive reciprocal route to higher-order exceptional degeneracies with independent control over intrinsic loss, near-field coupling, and radiative access.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.13086",
  "author_total": 6,
  "authors": [
    {
      "name": "Shuang Wu"
    },
    {
      "name": "Ruizhi Dong"
    },
    {
      "name": "Nikolay Solodovchenko"
    },
    {
      "name": "Dongxing Mao"
    },
    {
      "name": "Andrey Bogdanov"
    },
    {
      "name": "Yong Li"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bppje8qm4rz60.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.13086",
  "fulltext_url": null,
  "id": "bppje8qm4rz60",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.13086",
  "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.app-ph"
    ],
    [
      "arxiv",
      "physics.class-ph"
    ],
    [
      "arxiv",
      "physics.optics"
    ],
    [
      "openalex",
      "3107|Quantum Mechanics and Non-Hermitian Physics"
    ]
  ],
  "openalex": "W7212864341",
  "pdf_url": "https://arxiv.org/pdf/2609.13086",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-11",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bppje8qm4rz60.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:07Z",
      "native_id": "2609.13086",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.13086"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.app-ph",
      "subfield": "applied-instrumentation"
    },
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "Experimental observation of exceptional bound states in the continuum",
  "title_text": "Experimental observation of exceptional bound states in the continuum",
  "type": "preprint",
  "updated_at": "2026-10-30T12:21:07Z",
  "url": "https://research.draconitic.com/paper/bppje8qm4rz60",
  "venue": "arXiv",
  "versions": []
}