{
  "abstract": "A film-thickness error of 8 nm, within the tolerance of commercial thin-film lithium niobate wafers, shifts the group-velocity dispersion $β_2$ at 1550 nm by about 28 ps$^2$ km$^{-1}$. We study numerically whether a segmented, non-volatile phase-change cladding can correct this error after fabrication. In mode solves of 3012 geometries, Sb$_2$S$_3$ switches $β_2$ by a median of 181 ps$^2$ km$^{-1}$ at a 40 nm strip thickness with no material absorption under the adopted optical constants, whereas Sb$_2$Se$_3$ reaches a comparable contrast at a median modal loss of 5.6 dB cm$^{-1}$. Because phase adds along the guide, four independently switched binary segments reach a two-dimensional region of the $(β_2,β_3)$ plane; eigenmode expansion supports this description at the junctions. Full-wave solves at 65 die geometries show that the segment states move with the die error, so the bit pattern is chosen from a per-die model: a spectral surrogate constrained by exact identities of the lossless Maxwell problem. Its accuracy within the training domain is similar to that of unconstrained baselines; it keeps $β_2$ and $β_3$ consistent, and its error at an unseen film thickness is 8.3 rather than 13.0 ps$^2$ km$^{-1}$. With a bare test ring and a second ring carrying a crystalline strip already on the mask, 96.8% of the dies are trimmed into $\\pm25$ ps$^2$ km$^{-1}$, scored on full-wave solutions. A thermal model gives a candidate write window for a 532 nm beam.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.02652",
  "author_total": 3,
  "authors": [
    {
      "name": "Shoumik Debnath"
    },
    {
      "name": "Anup Kumar Modak"
    },
    {
      "name": "Sudipta Saha"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0h6rqb2hn6x0r.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.02652",
  "fulltext_url": null,
  "id": "0h6rqb2hn6x0r",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.02652",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.optics"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.02652",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/0h6rqb2hn6x0r.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T12:20:59Z",
      "native_id": "2611.02652",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.02652"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "Physics-Informed Surrogate for Sb2S3 Dispersion Trimming in Thin-Film Lithium Niobate",
  "title_text": "Physics-Informed Surrogate for Sb2S3 Dispersion Trimming in Thin-Film Lithium Niobate",
  "type": "preprint",
  "updated_at": "2026-11-05T15:20:18Z",
  "url": "https://research.draconitic.com/paper/0h6rqb2hn6x0r",
  "venue": "arXiv",
  "versions": []
}