X-ray laser opens up new avenues of research in material science
Researchers have used ultra-short pulses of X-rays to film shock waves in diamonds. The study headed by DESY scientists opens up new possibilities for studying the properties of materials. Thanks to the extremely bright and short X-ray flashes, the researchers were able to follow the rapid, dynamic changes taking place in the shock wave with a high spatial as well as a high temporal resolution.
The team around DESY physicist Prof. Christian Schroer is presenting its results in the journal Scientific Reports. "With our experiment we are venturing into new scientific terrain," says the first author of the scientific paper, Dr. Andreas Schropp of DESY. "We have managed for the first time to use X-ray imaging to quantitatively determine the local properties and the dynamic changes of matter under extreme conditions."
For their pilot study, the scientists analysed diamond samples with the world's most powerful X-ray laser, the Linac Coherent Light Source LCLS at the SLAC National Accelerator Laboratory in the U.S. The researchers fixed a three centimetre long diamond strip, just 0.3 millimetre thick, in a specimen holder and triggered a shock wave with a brief flash from a powerful infrared laser that hit the narrow edge of the diamond; this pulse lasted 0.15 billionths of a second (150 picoseconds) and reached a power level of up to 12 trillion watts (12 terawatts) per square centimetre. The resulting shock wave shot through the diamond at about 72,000 kilometres per hour.
"In order to take snapshots of such rapid processes, you need to use extremely short exposure times," explains Schropp. The X-ray pulses produced by the LCLS last just 50 millionths of a billionth of a second (50 femtoseconds), allowing them to capture even the fastest movements. However, as the diamond sample was destroyed with every shot, the scientists had to repeat the experiment with identical specimens for each image, whereby each picture was taken a little later to show the shock wave at a slightly later time. Finally, they assembled these still images to create a film, as in a "flip book".
Using this film, the scientists were able to determine quantitatively the change in density due to the shock wave. The X-ray microscope specifically developed for this purpose, permits details of the sample down to 500 millionths of a millimetre (500 nanometres) to be resolved.
Together with the speed of sound measured, this allows the state of the diamond to be determined under conditions of extreme pressure. The analysis shows that the intense shock wave compresses the diamond - one of the hardest materials in the world - locally by almost ten percent.
This pilot study offers new insights into the structure of diamonds. "In view of the remarkable physical properties of diamond it continues to be important both scientifically and technologically," says Prof. Jerome Hastings of SLAC.
"We have for the first time directly imaged shock waves in diamond using X-rays, and this opens up new perspectives on the dynamic behaviour of diamond under high pressure." Material scientists are particularly interested in the complex behaviour behind the initial shock front, which can already be seen in these first images.
The scientists hope that by refining X-ray lasers and optimising the detector, the spatial resolution can be further improved to less than 100 nanometres, for instance also at the superconducting X-ray laser European XFEL that is currently being built from the DESY campus in Hamburg to the neighbouring town of Schenefeld.
Thanks to the penetrating properties of X-rays, this technique can be applied to virtually any solid material, such as iron or aluminium. "The method is important for a series of applications in material science and for describing the physical processes occurring inside planets," summarises Schroer.
Apart from DESY and SLAC, the Technical University of Dresden, the University of Oxford in the UK, and the Lawrence Livermore National Laboratory (LLNL) in the U.S. were also involved in the research.
Deutsches Elektronen-Synchrotron DESY is the leading German accelerator centre and one of the leading in the world. DESY is a member of the Helmholtz Association and receives its funding from the German Federal Ministry of Education and Research (BMBF) (90 per cent) and the German federal states of Hamburg and Brandenburg (10 per cent). At its locations in Hamburg and Zeuthen near Berlin, DESY develops, builds and operates large particle accelerators, and uses them to investigate the structure of matter. DESY's combination of photon science and particle physics is unique in Europe.
Imaging Shock Waves in Diamond with Both High Temporal and Spatial Resolution at an XFEL; Andreas Schropp, Robert Hoppe, Vivienne Meier, Jens Patommel, Frank Seiboth, Yuan Ping, Damien G. Hicks, Martha A. Beckwith, Gilbert W. Collins, Andrew Higginbotham, Justin S. Wark, Hae Ja Lee, Bob Nagler, Eric C. Galtier, Brice Arnold, Ulf Zastrau, Jerome B. Hastings & Christian G. Schroer; Scientific Reports, 2015; DOI: 10.1038/srep11089
Thomas Zoufal | EurekAlert!
Argon is not the 'dope' for metallic hydrogen
24.03.2017 | Carnegie Institution for Science
Researchers make flexible glass for tiny medical devices
24.03.2017 | Brigham Young University
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy