{
  "abstract": "The negatively charged nitrogen vacancy (NV-) center in diamond is a promising point defect for highly sensitive quantum sensing. The formation of high-density NV- centers is essential for improving sensitivity. We performed room-temperature electron beam irradiation (EBI) and annealing on nitrogen-doped high-pressure high-temperature diamond crystals, aiming to convert all substitutional nitrogen into NV structures by increasing EBI fluence. While the Ns0 to NV0 and NV- conversion process dominated at low EBI fluences, in a high-fluence region, NV0 and NV- center and Ns0 and Ns+ concentrations decreased with increasing EBI fluence, indicating the formation of unknown nitrogen-related defects such as the H3 center, which is a nitrogen and vacancy aggregation defect. Although H3 centers were observed at high EBI fluence, their annealing temperature of 1375 +- 25 °C was lower than the typically reported temperatures over 1600 °C. We attribute this low-temperature formation to vacancy-mediated nitrogen diffusion and aggregation.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2606.27723",
  "author_total": 8,
  "authors": [
    {
      "name": "Chikara Shinei"
    },
    {
      "name": "Yuta Masuyama"
    },
    {
      "name": "Jun Chen"
    },
    {
      "name": "Hiroshi. Abe"
    },
    {
      "name": "Masashi Miyakawa"
    },
    {
      "name": "Takashi Taniguchi"
    },
    {
      "name": "Takeshi Ohshima"
    },
    {
      "name": "Tokuyuki Teraji"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8e2taezf7v7z8.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.27723",
  "fulltext_url": null,
  "id": "8e2taezf7v7z8",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2606.27723",
  "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"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2606.27723",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-24",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/8e2taezf7v7z8.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:24:11Z",
      "native_id": "2606.27723",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.27723"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Vacancy-mediated nitrogen diffusion and aggregation via high-fluence electron beam irradiation in HPHT synthesized diamond crystal",
  "title_text": "Vacancy-mediated nitrogen diffusion and aggregation via high-fluence electron beam irradiation in HPHT synthesized diamond crystal",
  "type": "preprint",
  "updated_at": "2026-10-30T12:24:11Z",
  "url": "https://research.draconitic.com/paper/8e2taezf7v7z8",
  "venue": "arXiv",
  "versions": []
}