Thank You SLS

Since 2001, the Swiss Light Source SLS has been a catalyst for ground-breaking discoveries in physics, materials science, biology, and chemistry. The extremely bright X-ray light provided by the SLS has enabled researchers to take giant leaps in their understanding of the world around us.

Countless scientists in Switzerland and worldwide have collaborated at this remarkable facility, pushing the boundaries of scientific knowledge and unlocking new possibilities. As we approach the temporary shutdown for the SLS 2.0 upgrade, our beamline scientists look back on 22 years of brilliant science and achievements made possible by the SLS.

A huge area of impact made by the SLS was in the field of structural biology. Vincent Olieric has been a scientist at the protein crystallography beamlines since 2007. He thanks SLS for the light that has enabled researchers to solve around 10,000 protein structures of biological and medicinal significance. Many of these have contributed to major scientific breakthroughs such as the Nobel Prize-winning studies of the ribosome, G protein-coupled receptors, and CRISPR-Cas9 gene editing.

These groundbreaking achievements were only possible thanks to technical advancements made at SLS, including the revolutionary hybrid photon counting detectors that have transformed synchrotron science.

Light from the SLS has given insights into how catalysts work. Maarten Nachtegaal who leads the Operando X-ray Spectroscopy group, speaks about how operando X-ray spectroscopy enables complex chemical processes to be studied in action.

With this, Maarten and colleagues could study electrolysers, which are devices that use electricity to produce hydrogen from water. Thanks to light from the SLS, they could follow the catalytic species that participate in hydrogen formation under conditions of operation and prove that they form only when the material is active. This discovery has led to new ways to describe the catalytic activity and design new catalysts.

With the light of the SLS, scientists have developed new technologies to study the structure and nature of materials. Marianne Liebi, who leads the Structure and Mechanics of Advanced Materials group and is a tenure track assistant professor at EPFL, thanks SLS for the light that enabled her and colleagues to develop a revolutionary method to study the arrangement of nanostructures in macroscopic samples.

Known as tensor tomography, this method reveals information on the structure of mineralised collagen fibres that make up bones and teeth. It is also useful for studying packaging materials such as carbon fibre composite or new materials based on cellulose. With information on the structure, these materials can be made stronger and tougher.

The SLS has also enabled insights into a completely different type of material: quantum materials. Zooming right in on the weird and wonderful behaviour of electrons, these breakthroughs aid our understanding of phenomena such as high temperature superconductivity. Thorsten Schmitt, leader of the Spectroscopy of Quantum Materials group at PSI, speaks about discovering a new quasiparticle called the orbiton. Thorsten and colleagues were able to discover it with a method called resonant inelastic X-ray scattering, which they could push to new resolution thanks to the high flux and stability of the SLS in the soft X-ray range.

How does an insect beat its wings as it flies? With the light of the SLS, the technique of X-ray tomographic microscopy has enabled such insights.

Scientist at the TOMCAT beamline Federica Marone thanks SLS for the light that could reveal how flies accomplish very complex flying maneuvers: knowledge that will advance bio-inspired flying machine. Other milestones in imaging dynamic processes include studying the deformation of cardiac tissue in a beating heart, volcano magma flow and bubble coalescence during manufacturing of metallic foams.

Time-resolved measurements can reveal how electrons move in functional materials. Beamline scientist Grigory Smolentsev thanks the SLS for light that enabled him and colleagues to solve the mystery of how copper-based organic LEDs work on the nanosecond timescale. Knowledge of how this process works will help to develop more efficient and cheaper materials for large area lighting.

We finish in the field of materials science, where scientists have used SLS to shed light on the atomic structure of a range of technologically interesting materials, ranging from geological samples to alloys for 3D printing. Nicola Casati, who leads the Materials Science group at PSI, thanks SLS for the light that allowed his team to measure 50 000 samples in a week. From this starting point, the collaboration between scientists at SLS and industry have now pushed this count to an astounding 10,000 samples a day. With higher throughput, the materials scientists could open the door to broader accessibility of the SLS’s wonderful light.

What science did the SLS make possible for you? Join us in honouring the past 22 years of scientific and technical excellence by sharing these on social media with #ThankYouSLS!

Text: Federica Ricatto and Miriam Arrell