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Probing dynamics in quantum materials with femtosecond X-rays

Nature Reviews Materials (2018) | Download Citation

Abstract

Optical pulses are routinely used to drive dynamic changes in the properties of solids. In quantum materials, many new phenomena have been discovered, including ultrafast transitions between electronic phases, switching of ferroic orders and non-equilibrium emergent behaviours, such as photoinduced superconductivity. Understanding the underlying non-equilibrium physics requires detailed measurements of multiple microscopic degrees of freedom at ultrafast time resolution. Femtosecond X-rays are key to this endeavour, as they can probe the dynamics of structural, electronic and magnetic degrees of freedom. Here, we review a series of representative experimental studies in which ultrashort X-ray pulses from free-electron lasers have been used, opening up new horizons for materials research.

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Change history

  • Correction 12 June 2018

    This article was originally published with an error in the main text. The original sentence, “The on-resonance intensity includes a charge order contribution (grey shaded region, Fig. 2b), which disappears on a timescale shorter than that of the off-resonance intensity and is sensitive only to structural dynamics”, should have read: “The on-resonance intensity includes a charge order contribution (grey shaded region, Fig. 2b) that disappears on a timescale shorter than that of the off-resonance intensity, which is sensitive only to structural dynamics.”

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Acknowledgements

The authors acknowledge funding from the European Research Council (ERC) under the European Union’s Seventh Framework Programme (FP7/2007-2013)/ERC Grant No. 319286 (Q-MAC) and acknowledge support from the Deutsche Forschungsgemeinschaft through the Hamburg Centre for Ultrafast Imaging — Structure, Dynamics and Control of Matter at the Atomic Scale excellence cluster and the priority programme SFB925. M.B. acknowledges financial support from the Swiss National Science Foundation through an Early Postdoc Mobility Grant (P2BSP2_165352).

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  1. Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany

    • Michele Buzzi
    • , Michael Först
    • , Roman Mankowsky
    •  & Andrea Cavalleri

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All authors contributed equally to the preparation of this article.

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The authors declare no competing interests.

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Correspondence to Andrea Cavalleri.

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https://doi.org/10.1038/s41578-018-0024-9

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