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  • Review Article
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X-ray free-electron lasers

Abstract

With intensities 108–1010 times greater than other laboratory sources, X-ray free-electron lasers are currently opening up new frontiers across many areas of science. In this Review we describe how these unconventional lasers work, discuss the range of new sources being developed worldwide, and consider how such X-ray sources may develop over the coming years.

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Figure 1: An undulator selects only certain resonant wavelengths of the radiation emitted by an electron.
Figure 2: FEL operating principle.
Figure 3: The high-gain FEL mechanism in the rest frame of the electron beam, which is propagating left to right.

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McNeil, B., Thompson, N. X-ray free-electron lasers. Nature Photon 4, 814–821 (2010). https://doi.org/10.1038/nphoton.2010.239

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