Focus |

X-ray Free Electron Lasers

XFELs can access new spatial and temporal scales, opening exciting possibilities for various areas of science.  But making XFEL science routine is challenging. New detectors are needed and the management and analysis of the huge volumes of data produced by high repetition facilities is difficult. User accessibility needs to broadened both in terms of numbers and expertise required to run experiments and facilities need to cater for the varied needs of different user communities. To fully exploit the potential of XFELs, users and beam scientists need to undergo a cultural change and rethink future experiments and the operation of these facilities.


X-ray free-electron lasers (XFELs) have rapidly developed into unique tools for probing diverse systems of interest to different scientific disciplines with angstrom–femtosecond resolution. Claudio Pellegrini provides an overview of the milestones in the development of XFELs and their unique capabilities.

Comment | | Nature Reviews Physics

X-ray free-electron lasers (XFELs) are unique tools that are making possible time-resolved measurements of structural and electronic dynamics at the quantum spatial and temporal scales. Jonathan Marangos discusses the transformative scientific potential of this capability but also stresses the importance of lowering barriers to access to maximize scientific reach.

Comment | | Nature Reviews Physics

The development of a new generation of detectors has been key to the success of X-ray free-electron lasers (XFELs). Anna Bergamaschi, Aldo Mozzanica and Bernd Schmitt discuss the advances in detector technology made over the past 10 years and examine the challenges presented by emerging high-repetition-rate XFEL facilities.

Comment | | Nature Reviews Physics

The European XFEL is the first hard X-ray high-repetition-rate free-electron laser facility. Sakura Pascarelli, Serguei Molodtsov and Thomas Tschentscher, scientific directors of the European XFEL, discuss the challenges that lie ahead before the European XFEL can reach its full potential and cater for an international and diverse community of users.

Comment | | Nature Reviews Physics

The first decade of X-ray free-electron lasers (XFELs) has led to technological advances and scientific discoveries, but has also highlighted several facility-level challenges. Chi-Chang Kao, Director of SLAC, discusses the lessons to be learned from the first 10 years of operation and shares his thoughts on how facilities can overcome challenges facing XFEL development.

Comment | | Nature Reviews Physics

The rise of machine learning is moving research away from tightly controlled, theory-guided experiments towards an approach based on data-driven searches. Abbas Ourmazd describes how this change might profoundly affect our understanding and practice of physics.

Comment | | Nature Reviews Physics


Over the past decade, several X-ray free-electron laser (XFEL) facilities have been constructed and started operation worldwide. New, high-repetition XFELs are expected to open to users in the next 5 years.

Research Highlight | | Nature Reviews Physics


This month in a dedicated Focus issue, we look back at the first decade of X-ray free-electron lasers (XFELs) and forward to the challenges and opportunities lying ahead.

Editorial | | Nature Reviews Physics