How a brilliant Berlin light source is accelerating innovations from green hydrogen to cancer treatments, one atom at a time.
Imagine a microscope so powerful it can track individual atoms moving within a battery while it's charging, or map the 3D structure of a virus protein to stop a pandemic in its tracks.
At the Helmholtz-Zentrum Berlin (HZB), this isn't science fiction—it's daily reality. For over 25 years, the BESSY II synchrotron light source has served as one of the world's most advanced "materials discovery machines," shining extremely bright, focused light on materials to reveal their deepest secrets 1 7 .
Developing affordable green hydrogen technologies and efficient solar cells
Accelerating drug development and improving medical treatments
Designing faster, more energy-efficient electronic devices
At its core, BESSY II is a third-generation 1.7 GeV storage ring that produces extremely bright, focused light across the ultraviolet and soft X-ray spectrum 7 . Think of it as a giant, sophisticated flashlight that can illuminate the atomic and molecular world.
This exceptional capability comes from BESSY II's sophisticated design, which provides unprecedented control over the energy, spatial, temporal, and polarization properties of the photon beam 7 . This means scientists can "tune" the light to specific needs—whether they're studying the magnetic properties of a new data storage material or observing chemical reactions in real-time.
BESSY II is far more than just a German facility—it serves an international community of scientists who submit over 1,200 research proposals annually 7 . Approximately 800 of these projects receive precious beamtime at the facility's 38 specialized experimental stations each year, resulting in about 500 scientific publications 7 . This vibrant collaborative ecosystem brings together the world's brightest minds to solve complex problems that no single institution could tackle alone.
The quest for sustainable energy solutions has been a major focus at BESSY II, with several recent breakthroughs:
BESSY II enables advances in electronics and data storage:
BESSY II enables research across multiple energy domains - from sustainable energy to medical applications
One of the most fascinating experiments at BESSY II addressed a fundamental scientific question: how can a liquid solution transition from being an electrical insulator to a metallic conductor? This phenomenon had been observed for decades—when alkali metals like sodium or potassium are dissolved in liquid ammonia, the solution changes color from blue to bronze as metal concentration increases—but the underlying atomic-level process remained mysterious 6 .
Understanding this transition isn't just academic curiosity; it has practical implications for developing better battery electrolytes and electronic capacitors 6 .
Creating precise cryogenic solutions of liquid ammonia with alkali metals at -60°C
Forming narrow liquid jets for study under ultra-high vacuum conditions
Directing soft X-rays at jets and using photoelectron spectroscopy
Developing computer models to predict electronic structure
The experiment yielded spectacular insights into the transition process:
| Metal Concentration | Observed Color | Electronic Structure | Electrical Behavior |
|---|---|---|---|
| Low | Blue | Isolated electrons & dielectrons | Insulating |
| Medium | Deep Blue | Mix of isolated & beginning collective states | Transitional |
| High | Golden-Bronze | Fully developed conduction band | Metallic |
The experiment successfully captured the precise moment when isolated electrons dissolved in solution begin to interact strongly enough to form a shared conduction band—the essential property of metals 6 .
| Equipment/Material | Function | Application Examples |
|---|---|---|
| Femtoslicing Beamline | Enables time-resolved studies of ultrafast processes | Observing spin processes happening in femtoseconds |
| SOL³PES Instrument | Studies liquid jets under vacuum using photoelectron spectroscopy | Analyzing electronic structure of solutions 6 |
| PEEM (Photoemission Electron Microscope) | High-resolution magnetic imaging | Mapping magnetic domains in microflowers 5 |
| EMIL Laboratory | Comprehensive analysis under working conditions | Developing and testing new catalyst materials 1 7 |
| Cryogenic Systems | Maintain samples at extremely low temperatures | Studying liquid ammonia solutions 6 |
| Operando Sample Environments | Analyze materials during real-world operation | Testing batteries while charging, catalysts during reactions 7 |
Atomic-level resolution for detailed material analysis
Femtosecond resolution for observing rapid processes
Analysis under real working environments
The BESSY II+ upgrade program will serve as a bridge to the future, expanding capabilities in electrochemistry and catalysis while maintaining leadership in quantum materials and life sciences 4 7 .
Looking further ahead, the BESSY III successor source is scheduled to begin operation in the mid-2030s 4 . Designed as a "materials discovery machine," BESSY III will combine a state-of-the-art fourth-generation synchrotron source with the integrated research campus in Berlin-Adlershof and the quantitative measurement capabilities of Germany's national metrology institute 4 7 .
2023-2028
Mid-2030s
From unraveling the atomic secrets of sustainable energy materials to mapping the proteins of dangerous viruses, BESSY II continues to demonstrate how fundamental materials research can address society's most pressing challenges.
The brilliant light generated at this remarkable facility doesn't just illuminate samples in experimental chambers—it illuminates paths to a more sustainable, healthy, and technologically advanced future.
We were able for the first time to capture the photoelectron signal of the excess electrons in liquid ammonia.
This ability to see what was previously invisible—whether electrons arranging into metallic states or the atomic structure of a viral protein—represents the very essence of discovery. At BESSY II and its future successors, the light of discovery continues to burn brightly, guiding scientists as they develop the materials that will shape our world tomorrow.