{
  "abstract": "We extend the KTHNY theory of defect-mediated melting in two dimensions to the case of active solids exhibiting both non-reciprocal (odd) elasticity and Cosserat (micropolar) coupling. For perturbatively small values of non-reciprocity, melting still proceeds via defect unbinding, but the melting temperature shifts due to activity. However, at a threshold value of non-reciprocity, we discover a qualitatively distinct mechanism for 2D melting, which we call topological instability. This melting occurs through the proliferation of defect pairs at any temperature. We use a combination of field theory and simulations to characterize this zero-temperature transition in terms of the defect-pair fugacity. Surprisingly, for higher activity values, we find reentrant crystallization, where the quasi-long-range order survives even at temperatures for which the equilibrium crystal would melt. Although active solids present one realization of this topological instability, we envision core-energy-driven defect proliferation as a generic and unexplored route for two-dimensional melting.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.09500",
  "author_total": 3,
  "authors": [
    {
      "name": "Zory Davoyan"
    },
    {
      "name": "Aditya Jha"
    },
    {
      "name": "Anton Souslov"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fghz04m6bxq3x.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.09500",
  "fulltext_url": null,
  "id": "fghz04m6bxq3x",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.09500",
  "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.stat-mech"
    ],
    [
      "openalex",
      "2210|Advanced Materials and Mechanics"
    ]
  ],
  "openalex": "W7212161320",
  "pdf_url": "https://arxiv.org/pdf/2609.09500",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-08",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/fghz04m6bxq3x.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:12Z",
      "native_id": "2609.09500",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.09500"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.stat-mech",
      "subfield": "statistical-nonlinear"
    }
  ],
  "title": "Topological instability and reentrant crystallization in active solids",
  "title_text": "Topological instability and reentrant crystallization in active solids",
  "type": "preprint",
  "updated_at": "2026-10-30T12:20:12Z",
  "url": "https://research.draconitic.com/paper/fghz04m6bxq3x",
  "venue": "arXiv",
  "versions": []
}