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Phase-coherent, injection-seeded, table-top soft-X-ray lasers at 18.9 nm and 13.9 nm

Nature Photonics volume 2, pages 9498 (2008) | Download Citation


There is keen interest in generating intense, coherent, soft-X-ray beams for scientific and measurement applications1. Here, we report the demonstration of soft-X-ray lasers with essentially full spatial and temporal coherence operating at wavelengths below 20 nm, and in particular within the 13-nm spectral region, which is important for the manufacturing of computer chips using extreme uv lithography. Gain-saturated pulses were produced in dense laser-created plasmas by amplifying high-harmonic seed pulses in the 18.9-nm and 13.9-nm transitions of nickel-like molybdenum and silver ions, respectively. These results, obtained using an injection seeding technique that can also be applied to improve the temporal coherence of free-electron lasers, extend our ability to generate bright phase-coherent laser beams to significantly shorter wavelengths. Moreover, the experiments were conducted using a practical table-top laser2. These compact soft-X-ray lasers offer new scientific opportunities, such as high-resolution coherent imaging and phase-coherent probing of atomic and molecular systems, in small laboratory environments.

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We thank Yanwei Liu and D. Attwood for discussions concerning the coherence properties of these lasers. We also gratefully acknowledge the contribution of M. Larotonda and useful discussions with H. Kapteyn and M. Murnane. This work was supported by the National Science Foundation (NSF) Engineering Research Center programme (NSF Award EEC-0310717). M.B. acknowledges a Department of Energy fellowship (DE-FG02-97ER25308).

Author information


  1. National Science Foundation Engineering Research Center for Extreme Ultraviolet Science and Technology and Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523, USA

    • Y. Wang
    • , E. Granados
    • , F. Pedaci
    • , D. Alessi
    • , B. Luther
    • , M. Berrill
    •  & J. J. Rocca
  2. Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA

    • J. J. Rocca


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Correspondence to J. J. Rocca.

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