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  1. No Access

    Article

    Clocking Auger electrons

    Intense X-ray free-electron lasers (XFELs) can rapidly excite matter, leaving it in inherently unstable states that decay on femtosecond timescales. The relaxation occurs primarily via Auger emission, so excit...

    D. C. Haynes, M. Wurzer, A. Schletter, A. Al-Haddad, C. Blaga, C. Bostedt… in Nature Physics (2021)

  2. No Access

    Article

    Dual-energy electron beams from a compact laser-driven accelerator

    Ultrafast pump–probe experiments open the possibility to track fundamental material behaviour, such as changes in electronic configuration, in real time. To date, most of these experiments are performed using ...

    J. Wenz, A. Döpp, K. Khrennikov, S. Schindler, M. F. Gilljohann… in Nature Photonics (2019)

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    Article

    Attosecond time–energy structure of X-ray free-electron laser pulses

    The time–energy information of ultrashort X-ray free-electron laser pulses generated by the Linac Coherent Light Source is measured with attosecond resolution via angular streaking of neon 1s photoelectrons. The ...

    N. Hartmann, G. Hartmann, R. Heider, M. S. Wagner, M. Ilchen, J. Buck… in Nature Photonics (2018)

  4. Article

    Open Access

    Accurate prediction of X-ray pulse properties from a free-electron laser using machine learning

    Free-electron lasers providing ultra-short high-brightness pulses of X-ray radiation have great potential for a wide impact on science, and are a critical element for unravelling the structural dynamics of mat...

    A. Sanchez-Gonzalez, P. Micaelli, C. Olivier, T. R. Barillot… in Nature Communications (2017)

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    Article

    Measuring the temporal structure of few-femtosecond free-electron laser X-ray pulses directly in the time domain

    Short-wavelength free-electron lasers are now well established as essential and unrivalled sources of ultrabright coherent X-ray radiation. One of the key characteristics of these intense X-ray pulses is their...

    W. Helml, A. R. Maier, W. Schweinberger, I. Grguraš, P. Radcliffe… in Nature Photonics (2014)

  6. No Access

    Article

    Sub-femtosecond precision measurement of relative X-ray arrival time for free-electron lasers

    Some X-ray free-electron laser facilities are pushing towards sub-10 fs pulses, making it desirable to reduce errors in X-ray/optical delay measurements to the 1 fs level. Researchers have now demonstrated X-r...

    N. Hartmann, W. Helml, A. Galler, M. R. Bionta, J. Grünert… in Nature Photonics (2014)

  7. No Access

    Article

    Single-shot carrier–envelope phase measurement of few-cycle laser pulses

    Full characterization of single ultrashort laser pulses, as needed for attosecond metrology and spectroscopy, requires precise measurement of the offset between the electric field and pulse envelope, or carrie...

    T. Wittmann, B. Horvath, W. Helml, M. G. Schätzel, X. Gu, A. L. Cavalieri… in Nature Physics (2009)