{
  "abstract": "Solid-phase reactions offer a route to integrate superconductors into Ge/SiGe heterostructures, but forming high-quality superconducting layers near the buried Ge quantum well remains challenging. We investigate reactions of V, Ta, and Nb with elemental Ge and with the Si$_{0.2}$Ge$_{0.8}$ barrier of Ge/SiGe heterostructures at processing temperatures of 365-390 $^\\circ$C. Cross-sectional electron microscopy and low-temperature electrical transport show that deposition on Ge at 390 $^\\circ$C, in which approximately 2 nm metal increments are separated by growth stops for in-situ annealing, produces reactions throughout the deposited films and superconducting transitions at approximately 0.14 K for V-Ge, 2.1 K for Ta-Ge, and 2.8 K for Nb-Ge. The Nb-Ge layer has an out-of-plane critical field of approximately 0.8 T at 2.1 K. In the heterostructure samples, intermixing is confined to regions approximately 5-12 nm thick near the metal-SiGe interface, leaving a substantial residual metal layer. Microscopy and transport together suggest that this residual film dominates the measured superconducting response. These results establish low-temperature formation of superconducting refractory-metal-Ge layers while identifying the limited interfacial reaction as the principal obstacle to extending this approach toward the buried quantum well.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.05210",
  "author_total": 6,
  "authors": [
    {
      "name": "Sebastiaan R. Roelofs"
    },
    {
      "name": "Jan Cornelis Wolff"
    },
    {
      "name": "Nick van Loo"
    },
    {
      "name": "Karina L. Hudson"
    },
    {
      "name": "Giordano Scappucci"
    },
    {
      "name": "Greg P. Mazur"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/488tedxkgj2ce.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.05210",
  "fulltext_url": null,
  "id": "488tedxkgj2ce",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.05210",
  "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",
      "cond-mat.mtrl-sci"
    ],
    [
      "arxiv",
      "cond-mat.supr-con"
    ],
    [
      "openalex",
      "3103|Superconducting and THz Device Technology"
    ]
  ],
  "openalex": "W7220681224",
  "pdf_url": "https://arxiv.org/pdf/2610.05210",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-04",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/488tedxkgj2ce.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:01Z",
      "native_id": "2610.05210",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.05210"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Solid-state reaction synthesis of superconducting refractory-metal germanides for Ge/SiGe quantum devices",
  "title_text": "Solid-state reaction synthesis of superconducting refractory-metal germanides for Ge/SiGe quantum devices",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:01Z",
  "url": "https://research.draconitic.com/paper/488tedxkgj2ce",
  "venue": "arXiv",
  "versions": []
}