---
OA_place: repository
OA_type: green
_id: '21529'
abstract:
- lang: eng
  text: 'A central challenge in the emerging field of free-electron quantum optics
    is to achieve strong quantum interaction and single-photon nonlinearity between
    a flying free electron and a photonic mode. Existing schemes are intrinsically
    limited by electron diffraction, which puts an upper bound on the interaction
    length and, therefore, on the strength of quantum coupling and nonlinearity. Here,
    we propose “free-electron fibers”: effectively one-dimensional photonic systems
    where free electrons copropagate with two guided modes. The first mode applies
    a ponderomotive trap to the free electron, removing the limitations due to electron
    diffraction. The second mode strongly couples to the guided free electron with
    an enhanced coupling that is orders of magnitude larger than previous designs.
    The extended interaction lengths enabled by our scheme allow for strong single-photon
    nonlinearities mediated by free electrons. We predict novel quantum effects in
    our system such as deterministic single-photon emission and nonlinear multimode
    dynamics. Our proposal paves the way toward the realization of heralded macroscopic
    nonclassical light generation, deterministic single-photon sources, and quantum
    gates controlled by free-electron–photon interactions.'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Aviv
  full_name: Karnieli, Aviv
  last_name: Karnieli
- first_name: Charles
  full_name: Roques-Carmes, Charles
  id: e2e68fc9-6505-11ef-a541-eb4e72cc3e82
  last_name: Roques-Carmes
- first_name: Nicholas
  full_name: Rivera, Nicholas
  last_name: Rivera
- first_name: Shanhui
  full_name: Fan, Shanhui
  last_name: Fan
citation:
  ama: Karnieli A, Roques-Carmes C, Rivera N, Fan S. Strong coupling and single-photon
    nonlinearity in free-electron quantum optics. <i>ACS Photonics</i>. 2024;11(8):3401-3411.
    doi:<a href="https://doi.org/10.1021/acsphotonics.4c00908">10.1021/acsphotonics.4c00908</a>
  apa: Karnieli, A., Roques-Carmes, C., Rivera, N., &#38; Fan, S. (2024). Strong coupling
    and single-photon nonlinearity in free-electron quantum optics. <i>ACS Photonics</i>.
    American Chemical Society. <a href="https://doi.org/10.1021/acsphotonics.4c00908">https://doi.org/10.1021/acsphotonics.4c00908</a>
  chicago: Karnieli, Aviv, Charles Roques-Carmes, Nicholas Rivera, and Shanhui Fan.
    “Strong Coupling and Single-Photon Nonlinearity in Free-Electron Quantum Optics.”
    <i>ACS Photonics</i>. American Chemical Society, 2024. <a href="https://doi.org/10.1021/acsphotonics.4c00908">https://doi.org/10.1021/acsphotonics.4c00908</a>.
  ieee: A. Karnieli, C. Roques-Carmes, N. Rivera, and S. Fan, “Strong coupling and
    single-photon nonlinearity in free-electron quantum optics,” <i>ACS Photonics</i>,
    vol. 11, no. 8. American Chemical Society, pp. 3401–3411, 2024.
  ista: Karnieli A, Roques-Carmes C, Rivera N, Fan S. 2024. Strong coupling and single-photon
    nonlinearity in free-electron quantum optics. ACS Photonics. 11(8), 3401–3411.
  mla: Karnieli, Aviv, et al. “Strong Coupling and Single-Photon Nonlinearity in Free-Electron
    Quantum Optics.” <i>ACS Photonics</i>, vol. 11, no. 8, American Chemical Society,
    2024, pp. 3401–11, doi:<a href="https://doi.org/10.1021/acsphotonics.4c00908">10.1021/acsphotonics.4c00908</a>.
  short: A. Karnieli, C. Roques-Carmes, N. Rivera, S. Fan, ACS Photonics 11 (2024)
    3401–3411.
date_created: 2026-03-30T12:22:47Z
date_published: 2024-07-29T00:00:00Z
date_updated: 2026-04-27T10:30:37Z
day: '29'
ddc:
- '530'
doi: 10.1021/acsphotonics.4c00908
extern: '1'
external_id:
  arxiv:
  - '2403.13071'
intvolume: '        11'
issue: '8'
keyword:
- quantum optics
- free electrons
- single photon nonlinearity
- electron-photon interaction
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2403.13071
month: '07'
oa: 1
oa_version: Preprint
page: 3401-3411
publication: ACS Photonics
publication_identifier:
  eissn:
  - 2330-4022
publication_status: published
publisher: American Chemical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Strong coupling and single-photon nonlinearity in free-electron quantum optics
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 11
year: '2024'
...
---
OA_place: publisher
OA_type: hybrid
_id: '21525'
abstract:
- lang: eng
  text: We present a novel design for an ultracompact, passive light source capable
    of generating ultraviolet and X-ray radiation, based on the interaction of free
    electrons with the magnetic near-field of a ferromagnet. Our design is motivated
    by recent advances in the fabrication of nanostructures, which allow the confinement
    of large magnetic fields at the surface of ferromagnetic nanogratings. Using ab
    initio simulations and a complementary analytical theory, we show that highly
    directional, tunable, monochromatic radiation at high frequencies could be produced
    from relatively low-energy electrons within a tabletop design. The output frequency
    is tunable in the extreme ultraviolet to hard X-ray range via electron kinetic
    energies from 1 keV to 5 MeV and nanograting periods from 1 μm to 5 nm. The proposed
    radiation source can achieve the tunability and monochromaticity of current free-electron-driven
    sources (free-electron lasers, synchrotrons, and laser-driven undulators), yet
    with a significantly reduced scale, cost, and complexity. Our design could help
    realize the next generation of tabletop or on-chip X-ray sources.
article_processing_charge: No
article_type: letter_note
arxiv: 1
author:
- first_name: Sophie
  full_name: Fisher, Sophie
  last_name: Fisher
- first_name: Charles
  full_name: Roques-Carmes, Charles
  id: e2e68fc9-6505-11ef-a541-eb4e72cc3e82
  last_name: Roques-Carmes
- first_name: Nicholas
  full_name: Rivera, Nicholas
  last_name: Rivera
- first_name: Liang Jie
  full_name: Wong, Liang Jie
  last_name: Wong
- first_name: Ido
  full_name: Kaminer, Ido
  last_name: Kaminer
- first_name: Marin
  full_name: Soljačić, Marin
  last_name: Soljačić
citation:
  ama: Fisher S, Roques-Carmes C, Rivera N, Wong LJ, Kaminer I, Soljačić M. Monochromatic
    X-ray source based on scattering from a magnetic nanoundulator. <i>ACS Photonics</i>.
    2020;7(5):1096-1103. doi:<a href="https://doi.org/10.1021/acsphotonics.0c00121">10.1021/acsphotonics.0c00121</a>
  apa: Fisher, S., Roques-Carmes, C., Rivera, N., Wong, L. J., Kaminer, I., &#38;
    Soljačić, M. (2020). Monochromatic X-ray source based on scattering from a magnetic
    nanoundulator. <i>ACS Photonics</i>. American Chemical Society . <a href="https://doi.org/10.1021/acsphotonics.0c00121">https://doi.org/10.1021/acsphotonics.0c00121</a>
  chicago: Fisher, Sophie, Charles Roques-Carmes, Nicholas Rivera, Liang Jie Wong,
    Ido Kaminer, and Marin Soljačić. “Monochromatic X-Ray Source Based on Scattering
    from a Magnetic Nanoundulator.” <i>ACS Photonics</i>. American Chemical Society
    , 2020. <a href="https://doi.org/10.1021/acsphotonics.0c00121">https://doi.org/10.1021/acsphotonics.0c00121</a>.
  ieee: S. Fisher, C. Roques-Carmes, N. Rivera, L. J. Wong, I. Kaminer, and M. Soljačić,
    “Monochromatic X-ray source based on scattering from a magnetic nanoundulator,”
    <i>ACS Photonics</i>, vol. 7, no. 5. American Chemical Society , pp. 1096–1103,
    2020.
  ista: Fisher S, Roques-Carmes C, Rivera N, Wong LJ, Kaminer I, Soljačić M. 2020.
    Monochromatic X-ray source based on scattering from a magnetic nanoundulator.
    ACS Photonics. 7(5), 1096–1103.
  mla: Fisher, Sophie, et al. “Monochromatic X-Ray Source Based on Scattering from
    a Magnetic Nanoundulator.” <i>ACS Photonics</i>, vol. 7, no. 5, American Chemical
    Society , 2020, pp. 1096–103, doi:<a href="https://doi.org/10.1021/acsphotonics.0c00121">10.1021/acsphotonics.0c00121</a>.
  short: S. Fisher, C. Roques-Carmes, N. Rivera, L.J. Wong, I. Kaminer, M. Soljačić,
    ACS Photonics 7 (2020) 1096–1103.
date_created: 2026-03-30T12:22:47Z
date_published: 2020-04-01T00:00:00Z
date_updated: 2026-04-15T11:51:29Z
day: '01'
ddc:
- '530'
doi: 10.1021/acsphotonics.0c00121
extern: '1'
external_id:
  arxiv:
  - '1910.09629'
  pmid:
  - ' 32596415'
has_accepted_license: '1'
intvolume: '         7'
issue: '5'
keyword:
- X-ray sources
- free electrons
- nanostructure
- undulator
- synchrotron
- free-electron laser
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.1021/acsphotonics.0c00121
month: '04'
oa: 1
oa_version: Published Version
page: 1096-1103
pmid: 1
publication: ACS Photonics
publication_identifier:
  eissn:
  - 2330-4022
publication_status: published
publisher: 'American Chemical Society '
quality_controlled: '1'
scopus_import: '1'
status: public
title: Monochromatic X-ray source based on scattering from a magnetic nanoundulator
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 7
year: '2020'
...