HZB contributions to special edition on Ultrafast Dynamics with X-ray Methods
At the end of his contribution, Phillippe Wernet makes a great arch from the past (Opticae Thesaurus, 1572) of research with light to the future. © Wikimedia cc
In this theme issue leading researchers discuss
recent work on the ultrafast electronic and structural
dynamics of matter using a new generation of short
duration X-ray photon sources. © Royal Society
In the new special issue of the "Philosophical Transactions of the Royal Society of London", internationally renowned experts report on new developments in X-ray sources and ultrafast time-resolved experiments. HZB physicists have also been invited to contribute.
Almost 350 years after Isaac Newton's ground-breaking paper "Theory of Light and Colors (1671)", the world's oldest scientific journal “Philosophical Transactions” is now once again dedicated to light. The special issue on “Ultrafast Dynamics with X-ray Methods” is aimed at researchers who want to investigate biological, chemical or physical processes and obtain an overview of new developments in light sources and the methods available there. Dynamic processes in materials can be analyzed with high resolution and short pulses at X-ray light sources using ultrafast methods.
Femtoslicing and BESSY VSR
The special issue provides a comprehensive overview of current advances in the generation of ultra-short X-ray pulses by light sources such as Free Electron Lasers (FELs), High Harmonic Generation (HHG) laser sources and synchrotron radiation sources. An article in collaboration with Dr. Karsten Holldack, HZB, presents FEls and Laser sources but also classifies storage ring based methods such as “Femtoslicing” and BESSY VSR. These methods combine highly brilliant synchrotron light with a special time structure and thus allow to address unique experimental questions that cannot be answered at other sources. This complements and expands the portfolio of accelerator-based sources.
Ultra fast spectroscopy for photochemistry
An important contribution is dedicated to photochemistry, an area that focuses on processes such as photosynthesis, the dynamics of which are still largely unexplored. Using ultra-fast spectroscopy at FELs, HHG sources or at the synchrotron with BESSY VSR, methods are now available to measure in detail, for example, excitations of metallo-proteins and the subsequent reactions ; such experiments provide data that are indispensable, for example, for understanding photocatalysis of solar fuels. This article was written by Prof. Dr. Philippe Wernet, formerly a senior scientist at the HZB, and now a professor at Uppsala University, Sweden.
To the publications:
Measurement of ultrafast electronic and structural dynamics with X-rays; J. P. Marangos (ed.)
doi: 10.1098/rsta/377/2145
Recent Advances in Ultrafast X-ray Sources; Robert Schoenlein, Thomas Elsaesser, Karsten Holldack, Zhirong Huang, Henry Kapteyn, Margaret Murnane, Michael Woerner
doi: 10.1098/rsta.2018.0384
Chemical interactions and dynamics with femtosecond X-ray spectroscopy and the role of X-ray free-electron lasers; Philippe Wernet
doi: 10.1098/rsta.2017.0464
- The future of corals – what X-rays can tell usThis summer, it was all over the media. Driven by the climate crisis, the oceans have now also passed a critical point, the absorption of CO2 is making the oceans increasingly acidic. The shells of certain sea snails are already showing the first signs of damage. But also the skeleton structures of coral reefs are deteriorating in more acidic conditions. This is especially concerning given that corals are already suffering from marine heatwaves and pollution, which are leading to bleaching and finally to the death of entire reefs worldwide. But how exactly does ocean acidification affect reef structures?
Prof. Dr. Tali Mass, a marine biologist from the University of Haifa, Israel, is an expert on stony corals. Together with Prof. Dr. Paul Zaslansky, X-ray imaging expert from Charité Berlin, she investigated at BESSY II the skeleton formation in baby corals, raised under different pH conditions. Antonia Rötger spoke online with the two experts about the results of their recent study and the future of coral reefs.
- Long-term stability for perovskite solar cells: a big step forwardPerovskite solar cells are inexpensive to produce and generate a high amount of electric power per surface area. However, they are not yet stable enough, losing efficiency more rapidly than the silicon market standard. Now, an international team led by Prof. Dr. Antonio Abate has dramatically increased their stability by applying a novel coating to the interface between the surface of the perovskite and the top contact layer. This has even boosted efficiency to almost 27%, which represents the state-of-the-art. After 1,200 hours of continuous operation under standard illumination, no decrease in efficiency was observed. The study involved research teams from China, Italy, Switzerland and Germany and has been published in Nature Photonics.
- Energy of charge carrier pairs in cuprate compoundsHigh-temperature superconductivity is still not fully understood. Now, an international research team at BESSY II has measured the energy of charge carrier pairs in undoped La₂CuO₄. Their findings revealed that the interaction energies within the potentially superconducting copper oxide layers are significantly lower than those in the insulating lanthanum oxide layers. These results contribute to a better understanding of high-temperature superconductivity and could also be relevant for research into other functional materials.