{
  "abstract": "We present the latest version of iGENE, a differentiable implementation of the local (flux-tube) gyrokinetic code GENE, now fully rewritten in JAX. iGENE features a multispecies, collisional, fully electromagnetic nonlinear gyrokinetic model while preserving end-to-end differentiability. The code is verified against GENE for linear ITG, TEM and KBM physics and for nonlinear turbulent fluxes with adiabatic and kinetic electrons. Forward-mode derivatives of the linear growth rate agree with finite differences for all five parameters tested, resolving the 30--50\\% discrepancy in $\\hat{s}$ and $ε$ reported for the earlier TensorFlow version. All collectives are native JAX operations, and the code strong-scales from 2 to 32 H100 GPUs with 86\\% parallel efficiency. We then assess three routes to a shorter time to solution. Custom CUDA FFT kernels operating in bfloat16 are up to $3.97\\times$ faster than fp32 cuFFT on the transforms, and on a single H100 iGENE is $2.63\\times$ faster per time step than single-precision GENE. Multi-rate sub-cycling of the parallel dynamics yields a further $1.89\\times$ speedup with kinetic electrons. Finally, a Hermite-Laguerre velocity-space representation is implemented, offering tunable fidelity.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.33561",
  "author_total": 4,
  "authors": [
    {
      "name": "Gabriele Merlo"
    },
    {
      "name": "Victor Artigues"
    },
    {
      "name": "Carl-Martin Pfeiler"
    },
    {
      "name": "Frank Jenko"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/63y780ykg0t0w.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.33561",
  "fulltext_url": null,
  "id": "63y780ykg0t0w",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.33561",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.plasm-ph"
    ],
    [
      "openalex",
      "3106|Magnetic confinement fusion research"
    ]
  ],
  "openalex": "W7223948686",
  "pdf_url": "https://arxiv.org/pdf/2610.33561",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-24",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/63y780ykg0t0w.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:35Z",
      "native_id": "2610.33561",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.33561"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.plasm-ph",
      "subfield": "plasma"
    }
  ],
  "title": "Accelerating high-fidelity gyrokinetic fusion simulations with iGENE",
  "title_text": "Accelerating high-fidelity gyrokinetic fusion simulations with iGENE",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:35Z",
  "url": "https://research.draconitic.com/paper/63y780ykg0t0w",
  "venue": "arXiv",
  "versions": []
}