{
  "abstract": "We report the first experimental realization and comprehensive characterization of a system consisting of two spatially separated superconducting waveguides coupled via a single transmon qubit. Since this system enables coherent control and the exchange of microwave photons between waveguides, and also holds the potential to serve as a scalable basic unit in quantum routing architectures, we will henceforth refer to it as a basic cell. The cell was characterized at 10 mK with an average input signal of ≈1 photon at ≈6 GHz, and with the qubit biased to its optimal point to minimize sensitivity to external magnetic fluctuations. By combining steady-state and time-domain measurements, we reconstructed the key parameters of the system, including qubit relaxation and dephasing, waveguide-qubit couplings, and cross-waveguide photon transfer efficiency. The observed performance is consistent with a non-Hermitian Hamiltonian formalism and demonstrates clear limits set by flux bias, temperature, and photon number, in agreement with flux- and temperature-induced dephasing models. Crucially, the cell operates reliably at the low-photon level, and in the high-photon regime we directly observe photon dressing induced by the qubit. These results establish a versatile platform for studying open quantum system phenomena and pave the way for scalable implementations of quantum routing and network nodes.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "name": "Evgeniya Mutsenik"
    },
    {
      "name": "Aidar Sultanov"
    },
    {
      "name": "Leonie Kaczmarek"
    },
    {
      "name": "Matthias Schmelz"
    },
    {
      "name": "Gregor Oelsner"
    },
    {
      "name": "Ronny Stolz"
    },
    {
      "name": "Evgeni Il’ichev"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5nnjb3n9km2g8.bib",
  "cited_by": 0,
  "doi": "10.1038/s41534-026-01399-5",
  "fulltext_url": null,
  "id": "5nnjb3n9km2g8",
  "issns": [
    "2056-6387"
  ],
  "landing_url": "https://www.nature.com/articles/s41534-026-01399-5",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0",
  "metadata_licence": null,
  "native_subjects": [],
  "openalex": null,
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-29",
  "publisher": "Springer Science and Business Media LLC",
  "ris": "https://research.draconitic.com/paper/5nnjb3n9km2g8.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:08Z",
      "native_id": "10.1038/s41534-026-01399-5",
      "source": "crossref",
      "url": "https://www.nature.com/articles/s41534-026-01399-5"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "issn:2056-6387",
      "subfield": "quantum"
    }
  ],
  "title": "Experimental characterization of the qubit-mediated coupling between two waveguides",
  "title_text": "Experimental characterization of the qubit-mediated coupling between two waveguides",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T00:20:43Z",
  "url": "https://research.draconitic.com/paper/5nnjb3n9km2g8",
  "venue": "npj Quantum Information",
  "versions": []
}