In a groundbreaking discovery, an international research team led by the University of Rostock and Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has successfully observed and characterized the structure of liquid carbon. This achievement, made possible through a collaboration with the Science and Technology Facilities Council (STFC) and the European X-ray Free Electron Laser (XFEL), unlocks new possibilities for understanding planetary interiors and advancing nuclear fusion technologies. The findings were published in 'Nature' on May 21, 2025.
Liquid carbon, a substance found within planets, holds immense potential for future technologies. The experiment, conducted at the European XFEL near Hamburg, Germany, utilized the UK-built DiPOLE 100-X (D100-X) laser to liquefy solid carbon samples for mere billionths of a second. Simultaneously, the X-ray beam captured diffraction patterns, revealing the atomic arrangement within the liquid carbon.
"This is the first time we have ever been able to observe the structure of liquid carbon experimentally," said Professor Dominik Kraus, Head of Carbon Working Group from the University of Rostock and HZDR. The measurements revealed that liquid carbon, with four nearest neighbors, exhibits structural similarities to solid diamond. This precise knowledge is crucial for accurate planetary modeling and for developing nuclear fusion power generation concepts.
The STFC's DiPOLE 100 laser technology, soon to be available at the Extreme Photonics Application Centre (EPAC) in the UK, promises to revolutionize future research. According to Professor John Collier, Director of STFC CLF, the D100-X system represents years of UK expertise, enabling measurements once deemed impossible. This breakthrough paves the way for quicker, more efficient experiments, potentially unlocking further secrets of extreme states of matter.