{
  "abstract": "Optical atomic clocks outperform the microwave clocks at the heart of current timing and navigation infrastructure by orders-of-magnitude, and recent progress in on-chip integration provides the opportunity to widely deploy them. Conventionally, a narrow linewidth laser interrogates the atomic transition, and an optical frequency comb divides its stabilised frequency (hundreds of terahertz) down to a microwave that is electronically countable. The laser(s) impose a significant size, weight, power and cost penalty, which is a current barrier to low-cost, scalable, fully on-chip optical clocks. Here, we position the frequency comb as the central engine of the clock by using Brillouin-amplified comb lines for atomic spectroscopy, which eliminates the need for stable clock lasers. Amplified comb lines reach an ultra-low frequency noise floor of $6\\,\\mathrm{Hz^2/Hz}$ at $30\\,\\mathrm{kHz}$ offset, an order-of-magnitude below a high-end commercial fibre laser. We realize a clock based on the $\\mathrm{5S}_{1/2}\\rightarrow\\mathrm{5D}_{5/2}$ transition in $^{87}\\mathrm{Rb}$ with competitive fractional frequency stability of $2\\times10^{-13}$ at $τ= 1\\,\\mathrm{s}$, averaging to $9\\times10^{-15}$ at $τ= 1000\\,\\mathrm{s}$. Lastly, we demonstrate a photonic chip-integrated Brillouin amplifier with a record 62.9 dB gain and up to 40 dB transferred noise suppression when pumped with a simple, low-cost diode laser. This opens a new route to compact optical clocks and enables use of atomic transitions lacking low-noise lasers by broadening a comb to the required wavelength and amplifying single lines.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.03038",
  "author_total": 13,
  "authors": [
    {
      "name": "Ryan L. Russell"
    },
    {
      "name": "Lachlan Pointon"
    },
    {
      "name": "Sarah Katherine Scholten"
    },
    {
      "name": "Choon Kong Lai"
    },
    {
      "name": "Lisa-Sophie Haerteis"
    },
    {
      "name": "Cong Tinh Bui"
    },
    {
      "name": "Alvaro Casas Bedoya"
    },
    {
      "name": "Andreas Boes"
    },
    {
      "name": "Duk Yong Choi"
    },
    {
      "name": "Stephen J. Madden"
    },
    {
      "name": "Andre Luiten"
    },
    {
      "name": "Benjamin J. Eggleton"
    },
    {
      "name": "Moritz Merklein"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bjhm461sn0j9j.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.03038",
  "fulltext_url": null,
  "id": "bjhm461sn0j9j",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.03038",
  "language": null,
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.atom-ph"
    ],
    [
      "arxiv",
      "physics.optics"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.03038",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bjhm461sn0j9j.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T12:20:59Z",
      "native_id": "2611.03038",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.03038"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.atom-ph",
      "subfield": "amo"
    },
    {
      "field": "physics",
      "origin": "arxiv:physics.optics",
      "subfield": "optics-photonics"
    }
  ],
  "title": "Brillouin comb line amplifiers for optical atomic clocks",
  "title_text": "Brillouin comb line amplifiers for optical atomic clocks",
  "type": "preprint",
  "updated_at": "2026-11-05T15:20:18Z",
  "url": "https://research.draconitic.com/paper/bjhm461sn0j9j",
  "venue": "arXiv",
  "versions": []
}