Experiment reveals new options for synchrotron light sources

An international team has shown through a sensational experiment how diverse the possibilities for employing synchrotron light sources are. Accelerator experts from the Helmholtz-Zentrum Berlin (HZB), the German federal metrology institute Physikalisch-Technische Bundesanstalt (PTB), and Tsinghua University in Beijing have used a laser to manipulate electron bunches at PTB’s Metrology Light Source so that they emitted intense light pulses having a laser-like character. Using this method, specialised synchrotron radiation sources would potentially be able to fill a gap in the arsenal of available light sources and offer a prototype for industrial applications. The work was published on 24 February 2021 in the leading scientific publication Nature.

The most modern light sources for research are based on particle accelerators. These are large facilities in which electrons are accelerated to almost the speed of light, and then emit light pulses of a special character. In storage-ring-based synchrotron radiation sources, the electron bunches travel in the ring for billions of revolutions, then generate a rapid succession of very bright light pulses in the deflecting magnets. In contrast, the electron bunches in free-electron lasers (FELs) are accelerated linearly and then emit a single super-bright flash of laser-like light. Storage ring sources as well as FEL sources have facilitated advances in many fields in recent years, from deep insights into biological and medical questions to materials research, technology development, and quantum physics.

Combining the virtues of both systems

Now a Sino-German team has shown that a pattern of pulses can be generated in a synchrotron radiation source that combines the advantages of both systems. The synchrotron source delivers short, intense microbunches of electrons that produce radiation pulses having a laser-like character (as with FELs), but which can also follow each other closely in sequence (as with synchrotron light sources).

Read more on the HZB website

Image credit: © Tsinghua University