{
  "abstract": "Precision in nonequilibrium processes comes at a thermodynamic cost: suppressing fluctuations generally requires increased dissipation. Thermodynamic uncertainty relations (TURs) make this trade-off quantitative by linking current fluctuations to entropy production in classical stochastic dynamics. In the decade since its discovery, the canonical steady-state TUR and its finite-time generalizations have become a cornerstone of non-equilibrium thermodynamics, constraining the performance of molecular machines and allowing heat dissipation to be inferred from observable fluctuations. Whether the canonical TUR can be violated in a controlled quantum device remains an outstanding experimental question, in part because doing so requires resolving extremely small steady-state currents as well as their fluctuations. Here we experimentally show that steady-state quantum transport can surpass the precision permitted by the canonical TUR. We observe this violation in a superconducting quantum thermal machine coupled to a microwave waveguide acting as a cold bath and to a classical noise source providing an effective infinite-temperature bath. We observe a TUR ratio $Q = 1.71 \\pm 0.17$, in violation of the classical bound $Q \\geq 2$. Our results demonstrate a fundamental distinction between classical and quantum thermodynamics, paving the way for quantum thermal devices that achieve enhanced precision at reduced energy cost.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.37149",
  "author_total": 7,
  "authors": [
    {
      "name": "Simon Sundelin"
    },
    {
      "name": "Ludvig Nordqvist"
    },
    {
      "name": "Khalak Mahadeviya"
    },
    {
      "name": "Vyom Kulkarni"
    },
    {
      "name": "Mohammed Ali Aamir"
    },
    {
      "name": "Mark T. Mitchison"
    },
    {
      "name": "Simone Gasparinetti"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/122jmv9ppzq7v.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.37149",
  "fulltext_url": null,
  "id": "122jmv9ppzq7v",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.37149",
  "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",
      "quant-ph"
    ],
    [
      "openalex",
      "3109|Advanced Thermodynamics and Statistical Mechanics"
    ]
  ],
  "openalex": "W7214973220",
  "pdf_url": "https://arxiv.org/pdf/2609.37149",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/122jmv9ppzq7v.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:31Z",
      "native_id": "2609.37149",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.37149"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "A quantum thermal machine surpassing the classical thermodynamic limit on precision",
  "title_text": "A quantum thermal machine surpassing the classical thermodynamic limit on precision",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:31Z",
  "url": "https://research.draconitic.com/paper/122jmv9ppzq7v",
  "venue": "arXiv",
  "versions": []
}