{
  "abstract": "Quantum key distribution (QKD) guarantees information-theoretic security by the laws of physics, but deployment at scale requires compact, manufacturable photonic terminals. Continuous-variable QKD (CV-QKD) is well suited for this transition through telecom-compatible, room-temperature coherent detection. However, unifying full on-chip core terminal integration, room-temperature operation, high loss tolerance, and composable end-to-end security in long-distance QKD remains a key bottleneck. Here we report a fully integrated CV-QKD platform in which two hybrid III--V/Si$_3$N$_4$ integrated lasers, a silicon transmitter, and a silicon coherent receiver implement the core terminal functions, operating with a local local oscillator (LLO) over fibre links of 25--150 km. A Bayesian machine-learning algorithm maintains robust phase lock throughout the long records required for composable security, consistently outperforming the conventional unscented Kalman filter, while rate-matched multidimensional reconciliation approaches the Shannon limit. The system certifies a composable finite-size secret-key rate of 29.3 kbps at 100 km from a 140-billion-symbol block, with 12.9 kbps at 125 km under finite-size analysis and 9.17 kbps at 150 km under asymptotic analysis. By establishing the longest finite-size and asymptotic reaches and the highest secret-key rate per symbol reported for integrated CV-QKD, this work advances the development of practical chip-based quantum networks.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.29200",
  "author_total": 9,
  "authors": [
    {
      "name": "Yankai Xu"
    },
    {
      "name": "Xinhang Li"
    },
    {
      "name": "Tao Wang"
    },
    {
      "name": "Jisheng Dai"
    },
    {
      "name": "Xueqin Jiang"
    },
    {
      "name": "Yuyao Guo"
    },
    {
      "name": "Peng Huang"
    },
    {
      "name": "Linjie Zhou"
    },
    {
      "name": "Guihua Zeng"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/74nd3hzsg3bn5.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.29200",
  "fulltext_url": null,
  "id": "74nd3hzsg3bn5",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.29200",
  "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",
      "quant-ph"
    ],
    [
      "openalex",
      "1702|Quantum Information and Cryptography"
    ]
  ],
  "openalex": "W7204933237",
  "pdf_url": "https://arxiv.org/pdf/2608.29200",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/74nd3hzsg3bn5.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:41Z",
      "native_id": "2608.29200",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.29200"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Fully integrated continuous-variable quantum key distribution with composable security over 100 km",
  "title_text": "Fully integrated continuous-variable quantum key distribution with composable security over 100 km",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:41Z",
  "url": "https://research.draconitic.com/paper/74nd3hzsg3bn5",
  "venue": "arXiv",
  "versions": []
}