{
  "annotation_id": "b03c35df-7af7-4d38-a688-0ae33170d29b",
  "date_created": "2026-03-02T18:01:21.757000Z",
  "date_modified": "2026-03-02T18:01:21.757000Z",
  "file_hash": "a42d49659ed0d893025d43b4ad481872c545df80dafb53c9d51ebeec88a31bde",
  "private": false,
  "record": {
    "abstract": "Reliable control of the deposition process of optical films and coatings\nfrequently requires monitoring of the refractive index profile throughout the\nlayer. In the present work a simple in situ approach is proposed which uses a\nWKBJ matrix representation of the optical transfer function of a single thin\nfilm on a substrate. Mathematical expressions are developed which represent the\nminima and maxima envelopes of the curves transmittance-vs-time and\nreflectance-vs-time. The refractive index and extinction coefficient depth\nprofiles of different films are calculated from simulated spectra as well as\nfrom experimental data obtained during PECVD of silicon-compound films.\nVariation of the deposition rate with time is also evaluated from the position\nof the spectra extrema as a function of time. The physical and mathematical\nlimitations of the method are discussed.",
    "arxiv_id": "physics/9804006",
    "authors": [
      "Daniel Poitras",
      "Ludvik Martinu"
    ],
    "categories": [
      "physics.optics"
    ],
    "doi": "10.1364/AO.37.004160",
    "title": "A simple method for the determination of slowly varying refractive index   profiles from in situ spectrophotometric measurements",
    "url": "https://arxiv.org/abs/physics/9804006"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "a50332eb-fdc1-482e-a01b-1848bcfbdbbd",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}