{
  "abstract": "Quantum key distribution (QKD) can deliver information-theoretic security, but its receivers are still typically assembled from cascaded bulk optics. Metasurfaces offer a radical reduction in this complexity. Here, we make the metasurface function as the QKD measurement device itself. We design wavelength-specific dielectric apertures at 780, 1550, 2000, and 10 600 nm that interweave the linear H/V and circular R/L phase libraries at a 0.44--0.49λ cell pitch, i.e., below half the operating wavelength, and map the complete passive-BB84 measurement directly onto four detector channels. This subwavelength basis co-location prevents an ordinary propagating-wave aperture mask from isolating one basis without simultaneously attenuating or perturbing the other. Simulated full-wave focal-plane intensities are converted directly into conditional Born probabilities using fitted, calibration-fixed detector regions. The selected designs achieve probability fidelities of 97.96--99.08%, four-port collected efficiencies of 17.43--40.94%, and mean intrinsic quantum bit error rates of 1.42--3.96%. At 1550 nm, the selected design gives an asymptotic device-level yield of 0.151 secret bits per incident photon under an ideal single-photon model. Six-state detector tomography gives positive both-basis security bounds for all six reconstructed receiver models, including their polarization-dependent loss, basis imbalance and crosstalk. These results establish protocol-matched meta-optics as a route to compact, passive QKD receivers.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.22946",
  "author_total": 2,
  "authors": [
    {
      "name": "Yan He"
    },
    {
      "name": "Adetunmise C. Dada"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1xbkx77x98qk1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.22946",
  "fulltext_url": null,
  "id": "1xbkx77x98qk1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.22946",
  "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",
      "1702|Quantum Information and Cryptography"
    ]
  ],
  "openalex": "W7214053434",
  "pdf_url": "https://arxiv.org/pdf/2609.22946",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-19",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/1xbkx77x98qk1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:19Z",
      "native_id": "2609.22946",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.22946"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    },
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Secure Quantum Metasurfaces for Direct Quantum Key Distribution Measurements",
  "title_text": "Secure Quantum Metasurfaces for Direct Quantum Key Distribution Measurements",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:19Z",
  "url": "https://research.draconitic.com/paper/1xbkx77x98qk1",
  "venue": "arXiv",
  "versions": []
}