{
  "abstract": "Recent studies of delocalization-localization transitions in disordered quantum chains have highlighted the role of rare, chain-breaking events that favor localization, in particular for high-energy eigenstates related to many-body localization. In this context, we revisit the random-field XXZ spin-1/2 chain at zero temperature with ferromagnetic interactions, equivalent to interacting fermions or hard-core bosons in a random potential with attractive interactions. We argue that localization in this model can be characterized by chain-breaking events, which are probed by the extreme values of simple local observables, such as the on-site density or the local magnetization, that are readily accessible in both experiments and numerical simulations. Adopting a bosonic language, we study the disorder-induced Berezinskii-Kosterlitz-Thouless (BKT) quantum phase transition from superfluid (SF) to Bose glass (BG), and focus on the strong disorder regime where localization is driven by weak links. Based on high-precision density matrix renormalization group simulations, we numerically show that extreme local densities accurately capture the BKT transition, even for relatively short chains ranging from a few dozen to a hundred sites. We also discuss the SF-BG transition in the weak disorder regime, where finite-size effects pose greater challenges. Overall, our work seeks to establish a solid foundation for using extreme statistics of local observables, such as density, to probe delocalization-localization transitions in disordered quantum chains, both in the ground state and at high energy.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2512.09029",
  "author_total": 5,
  "authors": [
    {
      "name": "Jeanne Colbois"
    },
    {
      "name": "Natalia Chepiga"
    },
    {
      "name": "Shaffique Adam"
    },
    {
      "name": "Gabriel Lemarié"
    },
    {
      "name": "Nicolas Laflorencie"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8apz9f9awn51s.bib",
  "cited_by": 0,
  "doi": "10.1088/1367-2630/ae9397",
  "fulltext_url": null,
  "id": "8apz9f9awn51s",
  "issns": [
    "1367-2630"
  ],
  "landing_url": "https://hal.science/hal-05412001v1",
  "language": "en",
  "licence": "CC-BY-NC-4.0",
  "licence_label": "CC BY-NC 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "hal",
      "0.phys"
    ],
    [
      "hal",
      "1.phys.cond"
    ],
    [
      "hal",
      "1.phys.qphy"
    ],
    [
      "hal",
      "2.phys.cond.cm-ds-nn"
    ],
    [
      "hal",
      "2.phys.cond.cm-sce"
    ],
    [
      "hal",
      "2.phys.cond.gas"
    ],
    [
      "openalex",
      "3107|Quantum many-body systems"
    ]
  ],
  "openalex": "W4417257384",
  "pdf_url": "https://hal.science/hal-05412001/document",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-02",
  "publisher": "Institute of Physics: Open Access Journals",
  "ris": "https://research.draconitic.com/paper/8apz9f9awn51s.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:46Z",
      "native_id": "hal-05412001",
      "source": "hal",
      "url": "https://hal.science/hal-05412001v1"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "hal:1.phys.cond",
      "subfield": "condensed-matter"
    },
    {
      "field": "physics",
      "origin": "hal:1.phys.qphy",
      "subfield": "quantum"
    }
  ],
  "title": "Extreme statistics as a probe of the superfluid to Bose-glass Berezinskii-Kosterlitz-Thouless transition",
  "title_text": "Extreme statistics as a probe of the superfluid to Bose-glass Berezinskii-Kosterlitz-Thouless transition",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:46Z",
  "url": "https://research.draconitic.com/paper/8apz9f9awn51s",
  "venue": "New Journal of Physics",
  "versions": []
}