{
  "abstract": "Thanks to low dissipation, superconducting devices are promising for a number of applications, such as detectors and implementations of quantum computation. However, their working can be adversely impacted by quasiparticles, which is why so-called quasiparticle poisoning mechanisms and their mitigation are under intense investigation. Here we focus on one poisoning mechanism, namely pair-breaking phonons, and its mitigation through down-conversion by a normal-metal film - the process in which scattering of high-energy phonons by electrons lowers the energy of the former below the pair-breaking threshold. To study the down-conversion, we introduce a model based on kinetic equations, which we solve both analytically (approximately) and numerically in the steady state. We use the solution to the estimate a properly-defined down-conversion efficiency which depends on material parameters (such as the strength of electron-phonon interaction and the phonon transmission coefficient at interfaces) and film and substrate thicknesses. Interestingly, we find that the efficiency is nearly optimal above a minimum metal thickness, typically between 50 and 500 nm depending on the metal-substrate combination.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2607.13870",
  "author_total": 2,
  "authors": [
    {
      "name": "Guglielmo La Magna"
    },
    {
      "name": "Gianluigi Catelani"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1dae65pd4fdhr.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2607.13870",
  "fulltext_url": null,
  "id": "1dae65pd4fdhr",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2607.13870",
  "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",
      "cond-mat.mes-hall"
    ],
    [
      "arxiv",
      "cond-mat.supr-con"
    ],
    [
      "arxiv",
      "quant-ph"
    ],
    [
      "openalex",
      "3103|Superconducting and THz Device Technology"
    ]
  ],
  "openalex": "W7168465476",
  "pdf_url": "https://arxiv.org/pdf/2607.13870",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-28",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/1dae65pd4fdhr.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:36:22Z",
      "native_id": "2607.13870",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2607.13870"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mes-hall",
      "subfield": "condensed-matter"
    },
    {
      "field": "physics",
      "origin": "arxiv:quant-ph",
      "subfield": "quantum"
    }
  ],
  "title": "Phonon down-conversion by normal metals for superconducting devices",
  "title_text": "Phonon down-conversion by normal metals for superconducting devices",
  "type": "preprint",
  "updated_at": "2026-11-01T12:20:44Z",
  "url": "https://research.draconitic.com/paper/1dae65pd4fdhr",
  "venue": "arXiv",
  "versions": []
}