{
  "abstract": "High-power, continuously tunable terahertz sources based on free-electron lasers require precise control of electron-beam microstructures. Quantitative prediction of the modulation amplitude across a broad frequency range remains challenging because the laser-induced distribution and its collective evolution must be treated together. To describe this coupled evolution, a nonlinear model is developed for microbunching seeded by a frequency-beating laser heater. The non-Gaussian heater-exit distribution is obtained by optical phase averaging and propagated through multistage compression in six-dimensional phase space. Source-induced correlations are retained, with space charge, coherent synchrotron radiation, and radio-frequency wakefields evaluated self-consistently. The wavelength-dependent bunching response is thereby connected to the laser beat frequency, laser power, and compression partition. The short-wavelength double peak is found to be governed mainly by longitudinal space charge, while bunching near a selected wavelength can be enhanced by redistributing compression at fixed total compression. The predicted source modulation and downstream response are benchmarked against Elegant and IMPACT-Z, respectively. Experimental measurements of the wavelength-dependent bunching factor at different laser pulse energies are found to agree well with the trends predicted by theory and simulation. The resulting framework provides a computationally efficient and predictive route to optimizing electron-beam microbunching for tunable, high-power terahertz generation at free-electron-laser facilities.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.18725",
  "author_total": 8,
  "authors": [
    {
      "name": "Wencai Cheng"
    },
    {
      "name": "Yin Kang"
    },
    {
      "name": "Kaiqing Zhang"
    },
    {
      "name": "Zhen Wang"
    },
    {
      "name": "Duan Gu"
    },
    {
      "name": "Guangling Chen"
    },
    {
      "name": "Chao Feng"
    },
    {
      "name": "Haixiao Deng"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5jntqk917y3qq.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.18725",
  "fulltext_url": null,
  "id": "5jntqk917y3qq",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.18725",
  "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.acc-ph"
    ],
    [
      "openalex",
      "2208|Particle Accelerators and Free-Electron Lasers"
    ]
  ],
  "openalex": "W7213515452",
  "pdf_url": "https://arxiv.org/pdf/2609.18725",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-16",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/5jntqk917y3qq.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:22:01Z",
      "native_id": "2609.18725",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.18725"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.acc-ph",
      "subfield": "applied-instrumentation"
    }
  ],
  "title": "Coherent collective amplification of terahertz microbunching seeded by laser frequency beating in relativistic electron beams",
  "title_text": "Coherent collective amplification of terahertz microbunching seeded by laser frequency beating in relativistic electron beams",
  "type": "preprint",
  "updated_at": "2026-10-30T12:22:01Z",
  "url": "https://research.draconitic.com/paper/5jntqk917y3qq",
  "venue": "arXiv",
  "versions": []
}