{
  "abstract": "We examine the thermal evolution of 100-nm-thick Pt$_{0.9}$Ni$_{0.1}$ alloy films on sapphire and langasite substrates with a 10-nm Zr adhesion layer. Sequential vacuum annealing from room temperature to 800 $^\\circ$C produces a substrate-dependent morphological pathway that is quantified by atomic force microscopy, image segmentation, height-distribution analysis, and effective coarsening metrics. Both types of films remain densely granular up to 400 $^\\circ$C, undergo a sharp coarsening transition between 400 and 600 $^\\circ$C, and evolve into coalesced faceted crystallites by 800 $^\\circ$C. The mean projected feature area increases from $7.84 \\times 10^2$ to $1.09 \\times 10^5$ nm$^2$ on langasite and from $3.32 \\times 10^2$ to $1.67 \\times 10^5$ nm$^2$ on sapphire. Sapphire therefore develops the larger faceted crystallites, while langasite exhibits the larger roughness maximum at 600 $^\\circ$C. Area distributions reveal that the 400-600 $^\\circ$C transition does not uniformly shift the initial granular population but instead replaces it with a distinct large-feature ensemble. Height and roughness measurements show a pronounced maximum at 600 $^\\circ$C, followed by partial smoothing at 800 $^\\circ$C, consistent with rapid coalescence followed by faceting-limited growth. An effective Arrhenius analysis based on $Δ\\langle r^2\\rangle$, with $\\langle r^2\\rangle = \\langle A\\rangle/π$, identifies the 400-600 $^\\circ$C interval as the dominant coarsening window. These results show that the thermal stability of PtNi/Zr films on sapphire and langasite is governed by the coupled influence of alloy mobility, interfacial energetics, and substrate-dependent morphological selection.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.09909",
  "author_total": 6,
  "authors": [
    {
      "name": "M. Awais Fiaz"
    },
    {
      "name": "M. Greenslit"
    },
    {
      "name": "R. J. Lad"
    },
    {
      "name": "Mauricio Pereira da Cunha"
    },
    {
      "name": "Luke Doucette"
    },
    {
      "name": "S. M. Hollen"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/99n2fzd3r3sxa.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.09909",
  "fulltext_url": null,
  "id": "99n2fzd3r3sxa",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.09909",
  "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",
      "cond-mat.mtrl-sci"
    ],
    [
      "openalex",
      "2206|Fluid Dynamics and Thin Films"
    ]
  ],
  "openalex": "W7202212427",
  "pdf_url": "https://arxiv.org/pdf/2608.09909",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-06",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/99n2fzd3r3sxa.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:48Z",
      "native_id": "2608.09909",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.09909"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Substrate-dependent thermally driven morphological evolution of Pt$_{0.9}$Ni$_{0.1}$ thin films on sapphire and langasite",
  "title_text": "Substrate-dependent thermally driven morphological evolution of Pt_0.9Ni_0.1 thin films on sapphire and langasite",
  "type": "preprint",
  "updated_at": "2026-10-30T12:19:48Z",
  "url": "https://research.draconitic.com/paper/99n2fzd3r3sxa",
  "venue": "arXiv",
  "versions": []
}