X-Ray Physics Group » Projects and funds
Projects and funds
BMBF
| Röntgen Angström Cluster BMBF Swedish Research Council 2020 – 2024 | Dynamics of proteins in crowded environments on multiple lengths and time scales |
| Universität Siegen Universität Tübingen Universität Lund Universität Stockholm DESY, Hamburg European XFEL, Hamburg MaxLab, Lund ESRF, Grenoble ILL, Grenoble | The scientific objective of this consortium is to explore the dynamics of proteins in crowded environments, in condensates, and during phase transitions on the relevant length and time scales. Protein dynamics on time scales from 10^-7 to 10^2 seconds will be measured by means of X-ray photon correlation spectroscopy (XPCS) at synchrotron and XFEL (X-ray free-electron laser) sources. These experiments will be complemented with neutron spectroscopy techniques such as neutron spin-echo (NSE) and neutron backscattering (NBS), which will give us access to the short-time dynamics of proteins on time scales ranging from 10-12 to 10-7 seconds. By making use of the synergy between XPCS and neutron spectroscopy, we will explore the full temporal and spatial window of protein dynamics in dense environments. |
| Verbundforschung BMBF 2019-2022 | BIO – XPCS |
| Universität Siegen DESY, Hamburg European XFEL, Hamburg | The objective of this project is to construct and commission a new set-up at beamline P10, DESY which allows investigating dynamics in the biological system by means of X-ray photon correlation spectroscopy (XPCS). |
| Röntgen Angström Cluster BMBF Swedish Research Council 2013-2016 | Soft matter in slow motion |
| Universität Siegen Universität Götheborg Universität Rostock DESY, Hamburg European XFEL, Hamburg | The objective of this project is to investigate slow dynamics in soft matter systems by means of X-ray photon correlation spectroscopy (XPCS). |
DFG
| DFG / NFDI | DAPHNE4NFDI |
| Siegen Berlin Kiel Tübingen Göttingen Wuppertal München Nürnberg DESY FZJ FRM II Hereon ESRF European XFEL EMBL | Making research Data fair for the X-ray and neutron scattering community in Germany. Developing schemes for metadata capture and archiving, developing electronic logbooks, developing analysis software for producing processed data, development of X-ray and neutron data repositories. Contributing to the construction of a national data infrastructure (NFDI) in Germany in collaboration with other partner consortia such as FAIRMAT, PUNCH4NFDI, MATWERK, NFDI4CHEM, NFDI4CAT. Introducing concepts of data management into university curricula. |
| DFG | Skin-depth resolved surface plasma dynamics of laser-excited dense-plasmas by grazing incidence X-ray surface scattering using X-ray free-electron laser |
| Universität Siegen European XFEL, Hamburg | The interaction of high-intensity lasers with solids creates high-density, warm-to-hot temperature plasmas involving a wide range of nonlinear physics phenomena. Such plasmas are not only of great relevance to astrophysics and inertial confinement fusion but also hold promise for the generation of bright, coherent light sources and for bright particle beams including ions. Here, efficiently depositing laser energy into plasmas is a key. In general, laser coupling into plasmas occur either in the under-critical density part of the expanding plasma-vacuum interface, where the laser wave propagates or within the skin depth of the overcritical plasma, where the laser wave is evanescent. The so-called critical density nc is located at a position in the density profile where the local electron plasma frequency equals the laser frequency, which is about 1% of the solid density for optical frequencies. It is known that a sub-μm scale density profile at the surface strongly influences the laser-plasma coupling. To obtain a complete picture of the laser-plasma coupling and the subsequent energy transport into the bulk, it is, therefore, crucial to know the dynamically changing over-critical plasma profile with nanometer (or skin-depth) resolution. Our project aims at visualizing surface plasmas employing X-ray free-electron lasers providing the required nm scale surface sensitivity on ultrafast time scales. |
| DFG | Depth-resolved distribution of ultrafast spin currents and fluctuations in magnetic structures |
| Universität Siegen | We propose to directly measure the ultrafast spatial evolution of laser-excited spin and charge densities inside magnetic multilayer samples employing ultrafast XUV and soft X-ray magnetic reflectivity experiments at HHG and XFEL sources. Using the coherence properties of the ultra-short FEL pulses we also aim at measuring the temporal fluctuations of spin and charge densities by means of resonant magnetic X-ray photon correlation spectroscopy. Both information, the temporal evolution of the spin and charge densities and their respective fluctuations will help to unravel the microscopic details of processes involved in ultrafast magnetization dynamics. |
| DFG | X-ray specular and off-specular diffuse scattering of magnetic interface structures at XFEL sources – investigating ultrafast spin transport processes |
| Universität Siegen | Recent experiments on fs time scales revealed unusual quenching mechanisms in magnetic multilayer systems, which hint towards a spatial component accompanying the demagnetization process. This is currently interpreted in terms of ultrafast spin-diffusion processes through magnetic materials and across interfaces yielding an ultrafast spin-dependent transport process. We want to study such magnetic interfaces using soft X-ray and XUV radiation in reflection geometry. This scattering geometry allows to map out the charge and spin density profiles of interfaces and surfaces of magnetic multilayer systems and to identify positions in reciprocal space being particular sensitive to changes in the spin-system. Using XFELs in the XUV regime we want to measure time-resolved the evolution of spin and charge profiles across interface structures upon irradiation with an ultra-short IR laser pulse. The experiments shall investigate details of the ultrafast spin diffusion processes across interface structures. Reflectivity yields details of the perpendicular density profile while the diffuse scattering channels allow to follow magnetic correlation lengths parallel to the interface in a depth resolved manner. Thus we want to map out the full available Q-space upon irradiation with an ultrashort laser pulse to follow the details of the space and time evolution of the corresponding spin profiles. The results will give unique insights into the physics of spin diffusion and transport processes across magnetic interface structures. |
others
| Eu-XFEL R&D Proposal | High-resolution characterization of high-intensity laser interaction with dense-plasmas using time-resolved grazing-incidence small-angle x-ray scattering (TR-GISAXS) |
| European XFEL Universität Siegen | The objective of this proposal is to provide the HED instrument with a capability of in-situ high-resolution characterization of the solid-density plasma surfaces under UHI laser interactions. This has not been achieved elsewhere in the world, thus will provide a unique capability to users to perform experiments in well-characterized and well-controlled manner. In addition, our project will also benefit high-pressure community users using nanosecond laser compression (another main pillar of HED/HIBEF), as the laser-absorption, subsequent electronic heat conduction and ion heating to initiate ablation at surface is a common issue here. |
Aktualisiert um 11:07 am 18. October 2021 von gg521