---
OA_place: repository
OA_type: green
_id: '21547'
abstract:
- lang: eng
  text: "Flatbands have become a cornerstone of contemporary condensed-matter physics\r\nand
    photonics. In electronics, flatbands entail comparable energy bandwidth and\r\nCoulomb
    interaction, leading to correlated phenomena such as the fractional\r\nquantum
    Hall effect and recently those in magic-angle systems. In photonics, they\r\nenable
    properties including slow light1 and lasing2. Notably, flatbands support\r\nsupercollimation—diffractionless
    wavepacket propagation—in both systems3,4.\r\nDespite these intense parallel efforts,
    flatbands have never been shown to affect the\r\ncore interaction between free
    electrons and photons. Their interaction, pivotal for\r\nfree-electron lasers5,
    microscopy and spectroscopy6,7, and particle accelerators8,9,\r\nis, in fact,
    limited by a dimensionality mismatch between localized electrons and\r\nextended
    photons. Here we reveal theoretically that photonic flatbands can overcome\r\nthis
    mismatch and thus remarkably boost their interaction. We design flatband\r\nresonances
    in a silicon-on-insulator photonic crystal slab to control and enhance the\r\nassociated
    free-electron radiation by tuning their trajectory and velocity. We observe\r\nsignatures
    of flatband enhancement, recording a two-order increase from the\r\nconventional
    diffraction-enabled Smith–Purcell radiation. The enhancement enables\r\npolarization
    shaping of free-electron radiation and characterization of photonic\r\nbands through
    electron-beam measurements. Our results support the use of\r\nflatbands as test
    beds for strong light–electron interaction, particularly relevant for\r\nefficient
    and compact free-electron light sources and accelerators."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Yi
  full_name: Yang, Yi
  last_name: Yang
- first_name: Charles
  full_name: Roques-Carmes, Charles
  id: e2e68fc9-6505-11ef-a541-eb4e72cc3e82
  last_name: Roques-Carmes
- first_name: Steven E.
  full_name: Kooi, Steven E.
  last_name: Kooi
- first_name: Haoning
  full_name: Tang, Haoning
  last_name: Tang
- first_name: Justin
  full_name: Beroz, Justin
  last_name: Beroz
- first_name: Eric
  full_name: Mazur, Eric
  last_name: Mazur
- first_name: Ido
  full_name: Kaminer, Ido
  last_name: Kaminer
- first_name: John D.
  full_name: Joannopoulos, John D.
  last_name: Joannopoulos
- first_name: Marin
  full_name: Soljačić, Marin
  last_name: Soljačić
citation:
  ama: Yang Y, Roques-Carmes C, Kooi SE, et al. Photonic flatband resonances for free-electron
    radiation. <i>Nature</i>. 2023;613:42-47. doi:<a href="https://doi.org/10.1038/s41586-022-05387-5">10.1038/s41586-022-05387-5</a>
  apa: Yang, Y., Roques-Carmes, C., Kooi, S. E., Tang, H., Beroz, J., Mazur, E., …
    Soljačić, M. (2023). Photonic flatband resonances for free-electron radiation.
    <i>Nature</i>. Springer Nature. <a href="https://doi.org/10.1038/s41586-022-05387-5">https://doi.org/10.1038/s41586-022-05387-5</a>
  chicago: Yang, Yi, Charles Roques-Carmes, Steven E. Kooi, Haoning Tang, Justin Beroz,
    Eric Mazur, Ido Kaminer, John D. Joannopoulos, and Marin Soljačić. “Photonic Flatband
    Resonances for Free-Electron Radiation.” <i>Nature</i>. Springer Nature, 2023.
    <a href="https://doi.org/10.1038/s41586-022-05387-5">https://doi.org/10.1038/s41586-022-05387-5</a>.
  ieee: Y. Yang <i>et al.</i>, “Photonic flatband resonances for free-electron radiation,”
    <i>Nature</i>, vol. 613. Springer Nature, pp. 42–47, 2023.
  ista: Yang Y, Roques-Carmes C, Kooi SE, Tang H, Beroz J, Mazur E, Kaminer I, Joannopoulos
    JD, Soljačić M. 2023. Photonic flatband resonances for free-electron radiation.
    Nature. 613, 42–47.
  mla: Yang, Yi, et al. “Photonic Flatband Resonances for Free-Electron Radiation.”
    <i>Nature</i>, vol. 613, Springer Nature, 2023, pp. 42–47, doi:<a href="https://doi.org/10.1038/s41586-022-05387-5">10.1038/s41586-022-05387-5</a>.
  short: Y. Yang, C. Roques-Carmes, S.E. Kooi, H. Tang, J. Beroz, E. Mazur, I. Kaminer,
    J.D. Joannopoulos, M. Soljačić, Nature 613 (2023) 42–47.
date_created: 2026-03-30T12:22:47Z
date_published: 2023-01-04T00:00:00Z
date_updated: 2026-04-27T09:10:26Z
day: '04'
ddc:
- '530'
doi: 10.1038/s41586-022-05387-5
extern: '1'
external_id:
  arxiv:
  - '2110.03550'
  pmid:
  - '36600060'
intvolume: '       613'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2110.03550
month: '01'
oa: 1
oa_version: Preprint
page: 42-47
pmid: 1
publication: Nature
publication_identifier:
  eissn:
  - 1476-4687
  issn:
  - 0028-0836
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Photonic flatband resonances for free-electron radiation
type: journal_article
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
volume: 613
year: '2023'
...