{
  "abstract": "Ferroelectric and antiferroelectric phases of LiTaO$_3$ compete under different electric boundary conditions. First-principles density-functional calculations show that the high-symmetry reference structure supports two relevant unstable $Γ$ modes: a polar $A_{2u}$ mode at $181i$ cm$^{-1}$ that condenses into the ferroelectric (FE) phase, and an antipolar $A_{2g}$ mode at $103i$ cm$^{-1}$ that condenses into the antiferroelectric (AFE) phase. Under short-circuit conditions the FE phase is the global minimum, with a well depth of $\\approx 144$ meV. Under open-circuit conditions the FE phase is destabilized by the unscreened depolarization field and the AFE phase becomes the ground state, with a well depth of $\\approx 19$ meV. A weakly unstable longitudinal-optic mode at $48.3i$ cm$^{-1}$ yields a well of only $\\approx 0.24$ meV and is thermodynamically irrelevant. Mapping the free energy versus electric displacement $D$ locates a second-order FE$\\leftrightarrow$AFE transition at $D_c=0.051$ C/m$^2$, lower than the corresponding $0.07$ C/m$^2$ in LiNbO$_3$ and therefore more accessible experimentally.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.27645",
  "author_total": 2,
  "authors": [
    {
      "name": "Eva Greene"
    },
    {
      "name": "Shaohui Qiu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5rf1vryqpcv2q.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.27645",
  "fulltext_url": null,
  "id": "5rf1vryqpcv2q",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.27645",
  "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.mtrl-sci"
    ],
    [
      "arxiv",
      "cond-mat.other"
    ],
    [
      "openalex",
      "2505|Ferroelectric and Piezoelectric Materials"
    ]
  ],
  "openalex": "W7204773114",
  "pdf_url": "https://arxiv.org/pdf/2608.27645",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-27",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/5rf1vryqpcv2q.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:22Z",
      "native_id": "2608.27645",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.27645"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "First-Principles DFT Study of Ferroelectric-to-Antiferroelectric Phase Transitions in LiTaO$_3$ under Electric Boundary Conditions",
  "title_text": "First-Principles DFT Study of Ferroelectric-to-Antiferroelectric Phase Transitions in LiTaO_3 under Electric Boundary Conditions",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:22Z",
  "url": "https://research.draconitic.com/paper/5rf1vryqpcv2q",
  "venue": "arXiv",
  "versions": []
}