First joint UA Ruhr appointment: Prof. Wang comes from Stanford to the Ruhr region

Professor Dr. Xijie Wang is known worldwide for his unique research experiments: He investigates how extremely rapid changes in materials can be made visible. Now he will establish the method of Mega-Electron-Volt Ultrafast Electron Diffraction (MeV-UED) at the two University alliance Ruhr universities and their physics departments. The University of Duisburg-Essen has appointed him for this purpose, and he has been seconded to TU Dortmund University on a 50 percent basis: He will conduct his cutting-edge research within the joint Research Center Chemical Sciences and Sustainability of the UA Ruhr. Prior to his move, Wang was a distinguished scientist at the SLAC National Accelerator Laboratory at the elite American university Stanford for ten years.

Wang is planning to build up a MeV-UED facility a unique experimental setup dedicated to both liquid phase chemistry and solid quantum materials. The DELTA Center for Synchrotron Radiation in Dortmund will be upgraded to accommodate the new experimental setup. This building not only guarantees the best conditions for the research of the highly respected physicist, but it will also become an important location for other scientists of the Research Center Chemical Sciences and Sustainability, plus it will strengthen the cutting-edge research in the RESOLV Cluster of Excellence of Ruhr University Bochum, the third partner in the University Alliance Ruhr.

Ultrafast electron diffraction enables the observation of natural processes with extremely high temporal resolution in the femtosecond range. The electrons used by Professor Wang almost reach the speed of light. “In the experiment, we shoot a very energetic beam of electrons at a material. When they hit atoms, the electrons 'bounce' off and are scattered in different directions. This scattering (or 'diffraction') creates a pattern that we see on a special screen. On this basis, we can make a movie that shows how the atoms are arranged and change in the material,” explains Professor Xijie Wang.

Wang developed MeV-UED at the turn of the millennium and has done widely recognized pioneering work in the application of this fastidious method. In 2019, he set up the world's first user facility for MeV-UED at SLAC, an “electron camera” which is now open to a broad scientific community. The potential is huge: “We can for example use ultrafast electron diffraction to find out how water and other substances behave during chemical and biological reactions, ” explains Wang. “This is a useful tool also in the development of more efficient solar cells, new medicines or technologies such as batteries.”

Wang's path led him to the USA after completing his physics degree at Shaanxi Normal University in China in 1982. His first stop there was the University of California Los Angeles, where he received his doctorate in 1992. He conducted research at Brookhaven National Laboratory for over 20 years, and thenmoved to the Stanford Linear Accelerator Center. Among other things, he was significantly involved in research into laser accelerators, high-brilliance electron beams and free electron X-ray lasers. In 2021, he received the prestigious Nuclear and Plasma Science Society’s Particle Accelerator Science and Technology Award from the Institute of Electrical and Electronics Engineers (IEEE), for outstanding contributions to the development of particle accelerator science.

He is also the author of numerous renowned publications that have attracted worldwide attention.