Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Megaelectronvolt electron acceleration driven by terahertz surface waves


Particles at relativistic energies form the basis of acceleration science. The emergence of terahertz-driven acceleration promises vastly smaller and cost-efficient accelerators; however, the field strength inside the acceleration structure has hitherto prevented the energy gain from reaching the megaelectronvolt range. Here we demonstrate an electron energy gain of up to 1.1 MeV and an effective acceleration gradient of up to 210 MV m−1 driven by terahertz surface waves, using their strong confinement to the waveguide and the fundamental transverse magnetic mode that is favourable for acceleration. The discrepancy in the velocity between the terahertz surface waves and electrons enables potential phase-space control, including temporal compression and spatial focusing. We expect these proof-of-principle results to enable the development of a tunable and highly efficient electron accelerator driven by terahertz surface waves for application in compact microscopy, radiation sources and cancer therapies.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Experimental setup.
Fig. 2: Energy modulations of the electrons.
Fig. 3: Simulation of the electron beam dynamics.
Fig. 4: Simulation results for compression and focusing.

Similar content being viewed by others

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. Source data are provided with this paper.


  1. Ishikawa, T. et al. A compact X-ray free-electron laser emitting in the sub-ångström region. Nat. Photonics 6, 540–544 (2012).

    Article  ADS  Google Scholar 

  2. Ishikawa, T. et al. Direct observation of collective modes coupled to molecular orbital-driven charge transfer. Science 350, 1501–1505 (2015).

    Article  ADS  Google Scholar 

  3. Yang, J. et al. Imaging CF3I conical intersection and photodissociation dynamics with ultrafast electron diffraction. Science 361, 64–67 (2018).

    Article  ADS  Google Scholar 

  4. Amaldi, U. Cancer therapy with particle accelerators. Nucl. Phys. A 654, 375C–399C (1999).

    Article  ADS  Google Scholar 

  5. Durante, M. & Loeffler, J. S. Charged particles in radiation oncology. Nat. Rev. Clin. Oncol. 7, 37–43 (2010).

    Article  Google Scholar 

  6. Strickland, D. & Mourou, G. Compression of amplified chirped optical pulses. Opt. Commun. 56, 219–221 (1985).

    Article  ADS  Google Scholar 

  7. Zhang, Z. X. et al. The 1 PW/0.1 Hz laser beamline in SULF facility. High Power Laser Sci. Eng. 8, e4 (2020).

    Article  ADS  Google Scholar 

  8. Wu, F. X. et al. Performance improvement of a 200 TW/1 Hz Ti:sapphire laser for laser wakefield electron accelerator. Opt. Laser Technol. 131, 106453 (2020).

    Article  Google Scholar 

  9. Vicario, C. et al. Generation of 0.9-mJ THz pulses in DSTMS pumped by a Cr:Mg2SiO4 laser. Opt. Lett. 39, 6632–6635 (2014).

    Article  ADS  Google Scholar 

  10. Jolly, S. W. et al. Spectral phase control of interfering chirped pulses for high-energy narrowband terahertz generation. Nat. Commun. 10, 2591 (2019).

    Article  ADS  Google Scholar 

  11. Zhang, B. L. et al. 1.4-mJ high energy terahertz radiation from lithium niobates. Laser Photon. Rev. 15, 2000295 (2021).

    Article  ADS  Google Scholar 

  12. Peralta, E. A. et al. Demonstration of electron acceleration in a laser-driven dielectric microstructure. Nature 503, 91–94 (2013).

    Article  ADS  Google Scholar 

  13. Sapra, N. V. et al. On-chip integrated laser-driven particle accelerator. Science 367, 79–83 (2020).

    Article  ADS  Google Scholar 

  14. Shiloh, R. et al. Electron phase-space control in photonic chip-based particle acceleration. Nature 597, 498–502 (2021).

    Article  ADS  Google Scholar 

  15. Nanni, E. A. et al. Terahertz-driven linear electron acceleration. Nat. Commun. 6, 8486 (2015).

    Article  ADS  Google Scholar 

  16. Zhang, D. F. et al. Segmented terahertz electron accelerator and manipulator (STEAM). Nat. Photonics 12, 336–342 (2018).

    Article  ADS  Google Scholar 

  17. Huang, W. R. et al. Terahertz-driven, all-optical electron gun. Optica 3, 1209–1212 (2016).

    Article  ADS  Google Scholar 

  18. Snively, E. C. et al. Femtosecond compression dynamics and timing jitter suppression in a THz-driven electron bunch compressor. Phys. Rev. Lett. 124, 6 (2020).

    Article  Google Scholar 

  19. Zhang, D. F. et al. Femtosecond phase control in high-field terahertz-driven ultrafast electron sources. Optica 6, 872–877 (2019).

    Article  ADS  Google Scholar 

  20. Hibberd, M. T. et al. Acceleration of relativistic beams using laser-generated terahertz pulses. Nat. Photonics 14, 755–759 (2020).

    Article  ADS  Google Scholar 

  21. Xu, H. X. et al. Cascaded high-gradient terahertz-driven acceleration of relativistic electron beams. Nat. Photonics 15, 426–430 (2021).

    Article  ADS  Google Scholar 

  22. Tang, H. et al. Stable and scalable multistage terahertz-driven particle accelerator. Phys. Rev. Lett. 24, 074801 (2021).

    Article  ADS  Google Scholar 

  23. Zhang, D. et al. Long range terahertz driven electron acceleration using phase shifters. Appl. Phys. Rev. 9, 031407 (2022).

    Article  ADS  Google Scholar 

  24. Zhang, D. F. et al. Cascaded multicycle terahertz-driven ultrafast electron acceleration and manipulation. Phys. Rev. X 10, 011067 (2020).

    Google Scholar 

  25. Wang, K. & Mittleman, D. M. Dispersion of surface plasmon polaritons on metal wires in the terahertz frequency range. Phys. Rev. Lett. 96, 157401 (2006).

    Article  ADS  Google Scholar 

  26. Stratton, J. A. In Electromagnetic Theory 524–545 (Wiley-IEEE Press, 2007).

  27. Russell, C. et al. Spectroscopy of polycrystalline materials using thinned-substrate planar Goubau line at cryogenic temperatures. Lab Chip 13, 4065–4070 (2013).

    Article  Google Scholar 

  28. Ayata, M. et al. High-speed plasmonic modulator in a single metal layer. Science 358, 630–632 (2017).

    Article  ADS  Google Scholar 

  29. Ummethala, S. et al. THz-to-optical conversion in wireless communications using an ultra-broadband plasmonic modulator. Nat. Photonics 13, 519–524 (2019).

    Article  Google Scholar 

  30. Ng, B. H. et al. Spoof plasmon surfaces: a novel platform for THz sensing. Adv. Opt. Mater. 1, 543–548 (2013).

    Article  Google Scholar 

  31. Ng, B. H. et al. Broadband terahertz sensing on spoof plasmon surfaces. ACS Photonics 1, 1059–1067 (2014).

    Article  Google Scholar 

  32. Wang, K., Barkan, A. & Mittleman, D. M. Propagation effects in apertureless near-field optical antennas. Appl. Phys. Lett. 84, 305–307 (2004).

    Article  ADS  Google Scholar 

  33. Wang, K. L. & Mittleman, D. M. Metal wires for terahertz wave guiding. Nature 432, 376–379 (2004).

    Article  ADS  Google Scholar 

  34. Tokita, S. et al. Collimated fast electron emission from long wires irradiated by intense femtosecond laser pulses. Phys. Rev. Lett. 106, 255001 (2011).

    Article  ADS  Google Scholar 

  35. Nakajima, H., Tokita, S., Inoue, S., Hashida, M. & Sakabe, S. Divergence-free transport of laser-produced fast electrons along a meter-long wire target. Phys. Rev. Lett. 110, 155001 (2013).

    Article  ADS  Google Scholar 

  36. Gibbon, P. Short Pulse Laser Interactions with Matter: An Introduction (Imperial College Press, 2005).

  37. Bocoum, M. et al. Anticorrelated emission of high harmonics and fast electron beams from plasma mirrors. Phys. Rev. Lett. 116, 185001 (2016).

    Article  ADS  Google Scholar 

  38. Thévenet, M. et al. Vacuum laser acceleration of relativistic electrons using plasma mirror injectors. Nat. Phys. 12, 355–360 (2015).

    Article  Google Scholar 

  39. Tian, Y. et al. Femtosecond-laser-driven wire-guided helical undulator for intense terahertz radiation. Nat. Photonics 11, 242–246 (2017).

    Article  ADS  Google Scholar 

  40. Zeng, Y. et al. Guiding and emission of milijoule single-cycle THz pulse from laser-driven wire-like targets. Opt. Express 28, 15258–15267 (2020).

    Article  ADS  Google Scholar 

  41. Rivera, N. & Kaminer, I. Light–matter interactions with photonic quasiparticles. Nat. Rev. Phys. 2, 538–561 (2020).

    Article  Google Scholar 

  42. Zhang, D. et al. Coherent surface plasmon polariton amplification via free-electron pumping. Nature 611, 55–60 (2022).

    Article  Google Scholar 

  43. CST (Dassault Systèmes, 2021);

Download references


We thank Y. Liao from the Shanghai Institute of Optics and Fine Mechanics and W. Chu from Zhangjiang Laboratory for support, advice and discussions. This work was funded by the National Key R&D Program of China (2022YFA1604401); the Strategic Priority Research Program (B) (grant number XDB16); the National Natural Science Foundation of China grants 11922412, 11874372 and 12104471; the Shanghai Pilot Program for Basic Research – Chinese Academy of Sciences, Shanghai Branch; the Key Research Program of Frontier Sciences, Chinese Academy of Sciences; the Youth Innovation Promotion Association of the Chinese Academy of Sciences; the Shanghai Sailing Program grant 21YF1453900; and the 100 Talents Program of the Chinese Academy of Sciences.

Author information

Authors and Affiliations



Y.-S.Z., X.-Q.Y., L.-W.S., X.-J.W. and Y.T carried out the experimental measurements; X.-Q.Y. and Y.-S.Z. analysed the results with discussions with Y.T., L.-W.S., X.-J.W. and R.-X.L.; Y.T., L.-W.S., X.-J.W. and R.-X.L. initiated early discussions on this topic. Y.T. and R.-X.L. conceived and supervised the project. All authors contributed to the project and the writing of the manuscript.

Corresponding authors

Correspondence to Li-Wei Song, Xiao-Jun Wu, Ye Tian or Ru-Xin Li.

Ethics declarations

Competing interests

Authors declare no competing interests.

Peer review

Peer review information

Nature Photonics thanks Nicholas Matlis, Emilio Nanni and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Extended Data Fig. 1 Comparison of the THz electric field inside the DLW.

a. A snapshot of the simulated electric field inside the DLW when free-space TM01 mode THz radiation was coupled by a focusing lens into the DLW. The energy coupling efficiency for this scenario was 52%, without considering the energy loss during mode conversion. b. Simulated THz field when an identical THz pulse was coupled to the DLW by a metal wire. Although the energy coupling efficiency was 85% for this situation (D = 10 mm), the maximal acceleration field (marked in blue) for the wire-coupling case is 2-fold larger than that of free-space coupling. This higher field strength c arises from the less dispersive waveform and hence the shorter pulse duration of the THz pulse owing to the almost dispersionless waveguiding nature of the THz surface wave on a metal wire.

Source data

Extended Data Fig. 2 Exemplification of the electron spectra for different values of D.

af Measured electron energy spectra. gl Integrated beam energy spectra corresponding to af. For comparison, four shots for each surface wave traveling distance D are exemplified. These shots are shown in gl with pink lines, where the highlighted red line indicates the mean value of the data. Note that, bifurcations in some of the spectra images arise possibly from the clockwise and anticlockwise electron trajectories as they revolve around the wire.

Source data

Extended Data Fig. 3 Electron energy distribution for ‘no THz inside the DLW’ condition.

The opaque red line indicates the mean value of 15 single-shot results with an FWHM spectrum width of 60% and a central energy of 1.7 MeV.

Source data

Extended Data Fig. 4 Transverse spatial distributions of the electrons impinging on the scintillation screen and recorded by the EMCCD.

a, the electrons were emitted directly from the wire. b, the electrons went through the DLW. Note that, in our experiment, since the iron shield with a 1-mm-diameter central hole is fixed 13 mm downstream of the DLW, the electron profiles shown here only represent those who have passed through the shield centre.

Source data

Supplementary information

Supplementary Information

Supplementary Figs. 1–4 and Discussion.

Supplementary Data 1

Source data for Supplementary Fig. 1.

Supplementary Data 2

Source data for Supplementary Fig. 2.

Supplementary Data 3

Source data for Supplementary Fig. 3.

Supplementary Data 4

Source data for Supplementary Fig. 4.

Source data

Source Data Fig. 1

Statistical source data for Fig. 1.

Source Data Fig. 2

Statistical source data for Fig. 2.

Source Data Fig. 3

Statistical source data for Fig. 3.

Source Data Fig. 4

Statistical source data for Fig. 4.

Source Data Extended Data Fig. 1

Statistical source data for Extended Data Fig. 1.

Source Data Extended Data Fig. 2

Statistical source data for Extended Data Fig. 2.

Source Data Extended Data Fig. 3

Statistical source data for Extended Data Fig. 3.

Source Data Extended Data Fig. 4

Statistical source data for Extended Data Fig. 4.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Yu, XQ., Zeng, YS., Song, LW. et al. Megaelectronvolt electron acceleration driven by terahertz surface waves. Nat. Photon. 17, 957–963 (2023).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing