{
  "abstract": "Strong light-matter and electron-phonon coupling generate ground states dressed by virtual bosonic excitations, making bare-state truncations and perturbative treatments unreliable in the ultrastrong-coupling regime. We introduce a nonperturbative variational ground-state framework based on a state-dependent polaron transformation, combined with a product-state ansatz and a second-order perturbative correction for residual matter-boson entanglement. We show that the optimized transformed frame becomes asymptotically decoupled at infinite coupling, because the leading linear coupling is canceled while off-diagonal matter transitions are suppressed by displaced-oscillator overlaps. The approach is asymptotically correct in both weak- and strong-coupling limits and remains accurate in the intermediate regime, where fixed polaron transformations are least reliable. Dicke-model benchmarks reproduce ground-state energies, fidelities, and the superradiant transition, with second-order energy errors below 0.2%. Holstein-model benchmarks yield errors below 0.5% and clarify how translational symmetry affects wave function quality. This dressed-basis framework enables nonperturbative modeling of strongly coupled light-matter and electron-phonon systems.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Chemical Science and Engineering, Graduate School of Engineering, Kyoto University, Kyoto615-8510, Japan."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 1,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Nguyen Thanh Phuc",
      "orcid": "0000-0002-8636-474X"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0gr1aa6ff0vtq.bib",
  "cited_by": 0,
  "doi": "10.1021/acs.jpclett.6c02011",
  "fulltext_url": "https://europepmc.org/articles/PMC13637079",
  "id": "0gr1aa6ff0vtq",
  "issns": [
    "1948-7185"
  ],
  "landing_url": "https://europepmc.org/article/MED/42917164",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3107|Strong Light-Matter Interactions"
    ]
  ],
  "openalex": "W7165119154",
  "pdf_url": "https://europepmc.org/articles/PMC13637079?pdf=render",
  "pmcid": "PMC13637079",
  "pmid": "42917164",
  "published": "2026-10-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/0gr1aa6ff0vtq.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:36Z",
      "native_id": "MED:42917164",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42917164"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3107|Strong Light-Matter Interactions",
      "subfield": "amo"
    }
  ],
  "title": "Variational Polaron Theory for Ground States of Strongly Coupled Light-Matter and Electron-Phonon Systems.",
  "title_text": "Variational Polaron Theory for Ground States of Strongly Coupled Light-Matter and Electron-Phonon Systems.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:20:36Z",
  "url": "https://research.draconitic.com/paper/0gr1aa6ff0vtq",
  "venue": "The journal of physical chemistry letters",
  "versions": []
}