Letter | Published:

Real-time observation of laser-driven electron acceleration

Nature Physics volume 7, pages 543548 (2011) | Download Citation

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Electron acceleration by laser-driven plasma waves1,2 is capableof producing ultra-relativistic, quasi-monoenergetic electron bunches3,4,5 with orders of magnitude higher accelerating gradients and much shorter electron pulses than state-of-the-art radio-frequency accelerators. Recent developments have shown peak energies reaching into the GeV range6 and improved stability and control over the energy spectrum and charge7. Future applications, such as the development of laboratory X-ray sources with unprecedented peak brilliance8,9 or ultrafast time-resolved measurements10 critically rely on a temporal characterization of the acceleration process and the electron bunch. Here, we report the first real-time observation of the accelerated electron pulse and the accelerating plasma wave. Our time-resolved study allows a single-shot measurement of the 5.8−2.1+1.9 fs electron bunch full-width at half-maximum (2.5−0.9+0.8 fs root mean square) as well as the plasma wave with a density-dependent period of 12–22 fs and reveals the evolution of the bunch, its position in the surrounding plasma wave and the wake dynamics. The results afford promise for brilliant, sub-ångström-wavelength ultrafast electron and photon sources for diffraction imaging with atomic resolution in space and time11.

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  • 21 March 2011

    In the version of this Letter originally published, the description of panels  c–i in the caption for Fig. 4 was incomplete. This error has now been corrected in all versions of the Letter.


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We thank M. Geissler for providing us with the ILLUMINATION code to perform the PIC simulations. This work is supported by DFG-Project Transregio TR18, by the Association EURATOM, Max-Planck-Institut für Plasmaphysik, by the Munich Centre for Advanced Photonics (MAP), by Laserlab-Europe/Labtech FP7 contract number 228334 and by the German Ministry of Education and Research (BMBF) under contract 03ZIK052. C.M.S.S. acknowledges the support of the Alexander von Humboldt Foundation. J.M.M. acknowledges the support of the Alexander von Humboldt Foundation and the Russian Foundation for Basic Research (RFBR), grant numbers 08-02-01245-a and 08-02-01137-a.

Author information


  1. Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany

    • Alexander Buck
    • , Karl Schmid
    • , Chris M. S. Sears
    • , Julia M. Mikhailova
    • , Ferenc Krausz
    •  & Laszlo Veisz
  2. Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching, Germany

    • Alexander Buck
    • , Karl Schmid
    •  & Ferenc Krausz
  3. Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität, 07743 Jena, Germany

    • Maria Nicolai
    • , Alexander Sävert
    •  & Malte C. Kaluza
  4. Helmholtz-Institut Jena, Helmholtzweg 4, 07743 Jena, Germany

    • Malte C. Kaluza


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A.B., M.N., K.S., C.M.S.S., A.S., M.C.K. and L.V. designed and carried out the experiments. A.B. and M.N. did the main data analysis. A.B. and J.M.M. performed the simulations. F.K., M.C.K. and L.V. provided overall guidance to the project. All authors discussed the results and contributed to the manuscript.

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The authors declare no competing financial interests.

Corresponding authors

Correspondence to Alexander Buck or Laszlo Veisz.

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