@inbook{12035,
  author = {Robert Schoenlein and Thomas Elsaesser and Karsten Holldack and Zhirong Huang and Henry Kapteyn and Margaret Murnane and Michael Woerner},
  title = {Recent advances in ultrafast X-ray sources},
  abstract = {Over more than a century, X-rays have transformed our understanding of the fundamental structure of matter and have been an indispensable tool for chemistry, physics, biology, materials science and related fields. Recent advances in ultrafast X-ray sources operating in the femtosecond to attosecond regimes have opened an important new frontier in X-ray science. These advances now enable: (i) sensitive probing of structural dynamics in matter on the fundamental timescales of atomic motion, (ii) element-specific probing of electronic structure and charge dynamics on fundamental timescales of electronic motion, and (iii) powerful new approaches for unravelling the coupling between electronic and atomic structural dynamics that underpin the properties and function of matter. Most notable is the recent realization of X-ray free-electron lasers (XFELs) with numerous new XFEL facilities in operation or under development worldwide. Advances in XFELs are complemented by advances in synchrotron-based and table-top laser-plasma X-ray sources now operating in the femtosecond regime, and laser-based high-order harmonic XUV sources operating in the attosecond regime.

This article is part of the theme issue ‘Measurement of ultrafast electronic and structural dynamics with X-rays’.},
  year = {2019},
  journal = {Philosophical Transactions Of The Royal Society A: Mathematical, Physical And Engineering Sciences},
  volume = {377},
  number = {2145},
  pages = {20180384},
  month = {2019-04},
  publisher = {Royal Society},
  address = {London},
  issn = {1364-503X},
  url = {https://royalsocietypublishing.org/doi/10.1098/rsta.2018.0384},
  doi = {10.1098/rsta.2018.0384},
}