{
  "abstract": "Strong interactions between particles can lead to emergent collective excitations. Spin waves, known as magnons, have been predicted to reach a strongly interacting hydrodynamic regime, where they form a slow collective density mode. In this work, we isolate exfoliated sheets of chromium trichloride (CrCl 3 ), where magnon interactions are strong, and develop a technique to measure the collective magnon dynamics though nearby nitrogen-vacancy centers in diamond. Thermal magnetic fluctuations generated by monolayer CrCl 3 increase upon decreasing temperature; this anomalous trend may be a consequence of the damping rate of a low-energy magnon sound mode that sharpens as magnon interactions increase with increasing temperature. By measuring the magnetic fluctuations emitted by thin multilayer CrCl 3 in the presence of a variable-frequency drive field, we obtain spectroscopic evidence for this two-dimensional magnon sound mode.",
  "abstract_shown": true,
  "affiliations": [
    "John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA",
    "Department of Physics, Harvard University, Cambridge, MA, USA",
    "Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA",
    "Department of Physics, Eidgenössische Technische Hochschule Zürich, Zurich, Switzerland",
    "Department of Electrical and Electronic Engineering, Tokyo Institute of Technology, Tokyo, Japan",
    "Institute for Theoretical Atomic, Molecular and Optical Physics (ITAMP), Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA",
    "Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel",
    "Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 15,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Ruolan Xue",
      "orcid": "0000-0001-5319-3537"
    },
    {
      "affs": [
        1
      ],
      "name": "Nikola Maksimovic",
      "orcid": "0000-0002-4540-6579"
    },
    {
      "affs": [
        1
      ],
      "name": "Pavel E. Dolgirev",
      "orcid": "0000-0003-4778-8694"
    },
    {
      "affs": [
        2
      ],
      "name": "Li-Qiao Xia",
      "orcid": "0000-0002-4267-763X"
    },
    {
      "affs": [
        3
      ],
      "name": "Aaron Müller",
      "orcid": "0000-0002-5148-9235"
    },
    {
      "affs": [
        4
      ],
      "name": "Ryota Kitagawa",
      "orcid": "0000-0002-8391-6019"
    },
    {
      "affs": [
        1,
        5
      ],
      "name": "Francisco Machado",
      "orcid": "0000-0003-0068-5073"
    },
    {
      "affs": [
        6,
        2
      ],
      "name": "Dahlia R. Klein",
      "orcid": "0000-0001-9581-2105"
    },
    {
      "affs": [
        2
      ],
      "name": "David MacNeill"
    },
    {
      "affs": [
        7
      ],
      "name": "Kenji Watanabe",
      "orcid": "0000-0003-3701-8119"
    },
    {
      "affs": [
        7
      ],
      "name": "Takashi Taniguchi",
      "orcid": "0000-0002-1467-3105"
    },
    {
      "affs": [
        2
      ],
      "name": "Pablo Jarillo‐Herrero",
      "orcid": "0000-0001-8217-8213"
    },
    {
      "affs": [
        1
      ],
      "name": "Mikhail D. Lukin",
      "orcid": "0000-0002-8658-1007"
    },
    {
      "affs": [
        3
      ],
      "name": "Eugene Demler",
      "orcid": "0000-0002-2499-632X"
    },
    {
      "affs": [
        1,
        0
      ],
      "name": "Amir Yacoby",
      "orcid": "0000-0002-5737-7963"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8ge7fwszwkrye.bib",
  "cited_by": 9,
  "doi": "10.1126/science.adp2397",
  "fulltext_url": null,
  "id": "8ge7fwszwkrye",
  "issns": [
    "0036-8075",
    "0193-4511",
    "1095-9203"
  ],
  "landing_url": "https://doi.org/10.1126/science.adp2397",
  "language": "en",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3107|Magnetic properties of thin films"
    ]
  ],
  "openalex": "W7161978075",
  "pdf_url": null,
  "pmcid": null,
  "pmid": "42166590",
  "published": "2026-05-21",
  "publisher": "American Association for the Advancement of Science",
  "ris": "https://research.draconitic.com/paper/8ge7fwszwkrye.ris",
  "sources": [
    {
      "first_seen": "2026-11-04T13:21:02Z",
      "native_id": "W7161978075",
      "source": "openalex",
      "url": "https://doi.org/10.1126/science.adp2397"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3107|Magnetic properties of thin films",
      "subfield": "amo"
    }
  ],
  "title": "Magnon hydrodynamics in an atomically thin ferromagnet",
  "title_text": "Magnon hydrodynamics in an atomically thin ferromagnet",
  "type": "peer-reviewed",
  "updated_at": "2026-11-06T13:20:25Z",
  "url": "https://research.draconitic.com/paper/8ge7fwszwkrye",
  "venue": "Science",
  "versions": []
}