{
  "abstract": "Silicon avalanche photodiodes provide a technologically mature platform for sensitive photodetection, but their spectral response is intrinsically limited by the silicon bandgap. Extending their operation into the infrared requires the integration of narrow-bandgap absorbers while preserving efficient avalanche multiplication and compatibility with silicon processing. Here, we propose and demonstrate a monolithic approach that combines direct, buffer-free growth of GeSn on silicon with a lateral thin-junction separate-absorption-multiplication architecture. The GeSn layer, with a Sn composition reaching 6 at.%, extends optical absorption to a wavelength of $2.6~μ$m, while avalanche multiplication is spatially confined to an ion-implanted silicon lateral junction. This separation enables independent control of infrared absorption and carrier multiplication without the thick Ge virtual substrates conventionally used for GeSn epitaxy. GeSn-on-Si avalanche photodiodes exhibit low pre-breakdown dark current, stable breakdown at 72 V independent of device diameter, and clear infrared photoresponse extending beyond $2~μ$m. At 78 K, the devices exhibit external quantum efficiency exceeding 100%, reaching 163% at $1.55~μ$m, providing direct evidence of avalanche multiplication. These results establish direct integration of narrow-bandgap group-IV absorbers with silicon multiplication regions as a scalable strategy for extending the spectral reach of silicon avalanche photodetection, opening a route toward monolithic infrared detectors for sensing, imaging, communications, LiDAR, and quantum photonics",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.27702",
  "author_total": 8,
  "authors": [
    {
      "name": "M. R. M. Atalla"
    },
    {
      "name": "J. Bélec"
    },
    {
      "name": "E. Rahier"
    },
    {
      "name": "S. Koelling"
    },
    {
      "name": "K. Omambac"
    },
    {
      "name": "P. Daoust"
    },
    {
      "name": "S. Assali"
    },
    {
      "name": "O. Moutanabbir"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/f1nan3cwmevt3.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.27702",
  "fulltext_url": null,
  "id": "f1nan3cwmevt3",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.27702",
  "language": null,
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.optics"
    ],
    [
      "openalex",
      "2208|Advanced Semiconductor Detectors and Materials"
    ]
  ],
  "openalex": "W7204799716",
  "pdf_url": "https://arxiv.org/pdf/2608.27702",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/f1nan3cwmevt3.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:00Z",
      "native_id": "2608.27702",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.27702"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "Extending Silicon Avalanche Photodetection Beyond $2~μ$m by Direct GeSn Integration",
  "title_text": "Extending Silicon Avalanche Photodetection Beyond 2 μm by Direct GeSn Integration",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:00Z",
  "url": "https://research.draconitic.com/paper/f1nan3cwmevt3",
  "venue": "arXiv",
  "versions": []
}