{
  "abstract": "A seminal result of Hastings showed that entangled inputs can increase the rate of classical communication through independent uses of a quantum channel. While Hastings' result proved the existence of this phenomenon, it has remained a major open problem to find an explicit channel with this property. In this work, we resolve this question by constructing an explicit family of finite-dimensional quantum channels for which entangling inputs between pairs of channel uses yields an unbounded separation from the achievable communication rate using unentangled inputs. We describe a circuit implementation of our channel that uses only deterministic qudit Clifford unitaries and a single binary measurement with classical feedforward. The key ingredient is a careful design of the measurement and feedforward process that yields the required one-copy and two-copy output entropy bounds from moment estimates alone, without requiring strong convergence of the underlying unitary family.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.26743",
  "author_total": 3,
  "authors": [
    {
      "name": "Hao-Chung Cheng"
    },
    {
      "name": "Benjamin Lovitz"
    },
    {
      "name": "Peixue Wu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/827dbv10cnxyy.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.26743",
  "fulltext_url": null,
  "id": "827dbv10cnxyy",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.26743",
  "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",
      "cs.IT"
    ],
    [
      "arxiv",
      "math-ph"
    ],
    [
      "arxiv",
      "math.IT"
    ],
    [
      "arxiv",
      "math.MP"
    ],
    [
      "arxiv",
      "quant-ph"
    ],
    [
      "openalex",
      "1702|Quantum Information and Cryptography"
    ]
  ],
  "openalex": "W7214111786",
  "pdf_url": "https://arxiv.org/pdf/2609.26743",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-05",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/827dbv10cnxyy.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:01Z",
      "native_id": "2609.26743",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.26743"
    }
  ],
  "subjects": [
    {
      "field": "mathematics",
      "origin": "arxiv:math-ph",
      "subfield": "mathematical-physics"
    },
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Explicit channels with unbounded gains in classical communication using entangled inputs",
  "title_text": "Explicit channels with unbounded gains in classical communication using entangled inputs",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:10Z",
  "url": "https://research.draconitic.com/paper/827dbv10cnxyy",
  "venue": "arXiv",
  "versions": []
}