{
  "annotation_id": "4b461966-5c5f-48cd-8fb5-ddb95a6e7a9e",
  "date_created": "2026-03-02T18:01:10.918000Z",
  "date_modified": "2026-03-02T18:01:10.918000Z",
  "file_hash": "d81638e576adfc4d5a4ec94c54575c924c091db8c8914a8e7bf4d6c5c6b8dea0",
  "private": false,
  "record": {
    "abstract": "The use of short lengths of large core phosphate glass fibre, doped with high\nconcentrations of Er or Er:Yb represents an attractive route to achieving high\npower erbium doped fibre amplifiers (EDFAs) and lasers (EDFLs). With the aim of\ninvestigating the potential of achieving diffraction limited output from such\nlarge core fibres, we present experimental results of fundamental mode\npropagation through a 20 cm length of passive 300 micrometer core multimode\nfibre when the input is a well-aligned Gaussian beam. Through careful control\nof fibre geometry, input beam parameters and alignment, we measured an output M\nsquared of 1.1 + - 0.05. The fibre had a numerical aperture of 0.389, implying\na V number of 236.8. To our knowledge, this is the largest core fibre through\nwhich diffraction limited fundamental mode propagation has been demonstrated.\nAlthough the results presented here relate to undoped fibre, they do provide\nthe practical basis for a new generation of EDFAs and EDFLs.",
    "arxiv_id": "physics/0607198",
    "authors": [
      "C. D. Stacey",
      "R. M. Jenkins",
      "J. Banerji",
      "A R Davies"
    ],
    "categories": [
      "physics.optics"
    ],
    "doi": "10.1016/j.optcom.2006.08.002",
    "title": "Demonstration of fundamental mode only propagation in highly multimode   fibre for high power EDFAs",
    "url": "https://arxiv.org/abs/physics/0607198"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "afa9f9d8-8af8-4362-8dac-63d29d92eda6",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}