{
  "abstract": "We theoretically investigate strong-coupling properties of an attractively interacting Fermi atomic gas, where the Cooper-pair formation occurs between atoms belonging to different dimensional bands. Including pairing fluctuations within the framework of the self-consistent $T$-matrix approximation (SCTMA), we examine how the BCS-type superfluid phase transition temperature $T_\\mathrm{c}$ varies as one moves from the 3D-3D to the 2D-3D system, in the wide parameter region with respect to the strength of the pairing interaction. In the 2D-3D limit, we find that, while the mean-field BCS theory predicts $T_\\mathrm{c}>0$ in the strong-coupling regime, $T_\\mathrm{c}$ is remarkably suppressed down to zero by pairing fluctuations that are strongly enhanced by the mixed-dimensionality of the system. As the origin of this, we clarify that the lower-dimensional (2D) component dominates the superfluid instability, so that the vanishing $T_\\mathrm{c}$ is the same phenomenon as that in the 2D-2D case. We also point out that this can already be seen in the mean-field level, when one examines the propagation of the Goldstone mode. On the other hand, we find that the pseudogap phenomenon, which is known as a precursor of Cooper-pair formation, exhibits a 3D character of the 2D-3D system. These results indicate that the dimensionality of a strongly interacting Fermi gas depends on what we observe.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: Phys. Rev. A 114, 033326 (2026)",
  "arxiv": "2605.30986",
  "author_total": 4,
  "authors": [
    {
      "name": "Haruka Takeda"
    },
    {
      "name": "Saki Hirai"
    },
    {
      "name": "Shumpei Iwasaki"
    },
    {
      "name": "Yoji Ohashi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fxbmfm2t146p3.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2605.30986",
  "fulltext_url": null,
  "id": "fxbmfm2t146p3",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2605.30986",
  "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.quant-gas"
    ],
    [
      "arxiv",
      "cond-mat.supr-con"
    ],
    [
      "arxiv",
      "physics.atom-ph"
    ],
    [
      "openalex",
      "3107|Cold Atom Physics and Bose-Einstein Condensates"
    ]
  ],
  "openalex": "W7163012725",
  "pdf_url": "https://arxiv.org/pdf/2605.30986",
  "pmcid": null,
  "pmid": null,
  "published": "2026-05-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/fxbmfm2t146p3.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:31Z",
      "native_id": "2605.30986",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2605.30986"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.quant-gas",
      "subfield": "amo"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.quant-gas",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Dimensionality of a strongly interacting 2D-3D Fermi-Fermi mixture from the perspective of superfluid instability and excitation properties",
  "title_text": "Dimensionality of a strongly interacting 2D-3D Fermi-Fermi mixture from the perspective of superfluid instability and excitation properties",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:31Z",
  "url": "https://research.draconitic.com/paper/fxbmfm2t146p3",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1103/2yrl-2h7h",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}