# PETRA IV Workshop - Earth, Environment, and Materials for Nanoscience and Information Technology

Nov 2 – 4, 2020
Online
Europe/Berlin timezone
This workshop will be held as an online event!

## Scientific Programme

1. Enabling Technology

PETRA IV will be the synchrotron radiation source with the highest spectral brightness worldwide, reaching the diffraction limit up to X-ray energies of about 10 keV. Due to the unique properties of the source, X-ray methods and techniques will be pushed to its limits and will gain significantly in performance.

The session will present and discuss current and future methods and techniques as well as their potential applications and opportunities in view of PETRA IV.

Organization:

K. Bagschik

2. Structure of Nanomaterials and Nanoparticles during growth, in-situ and operando conditions

Nanomaterials and nanoparticles find application in numerous fields ranging from structural materials to catalysis and medicine. The new storage ring of Petra IV will provide the ultimate X-ray beam properties to characterize nanomaterials, in order to answer crucial questions regarding synthesis and structure-property relationships, thereby bridging length scales from atomic to mesoscale structures. Such knowledge is essential for the basic understanding and design of next-generation nanomaterials with specific properties. By the use of extremely focused X-ray beams well below 100 nm containing photon fluxes comparable to present day 3rd generation storage rings, new scattering experiments will become feasible. These will include operando and in-situ studies on single nanoparticles and scanning techniques of larger ensembles or nanocomposite bulk materials with unprecedented spatial resolution. Existing techniques, which will become feasible on the local nanoscale, include 3D and 2D X-ray diffraction and total scattering methods. The enhanced x-ray beam coherence properties, especially at high energies, will open up new avenues towards high spatial resolution structure determination of nanomaterials, such as Bragg coherent diffraction imaging. Techniques that require highly coherent photon fluxes, such as nuclear resonant scattering, will become feasible with a high spatial resolution using focused nanobeams.

This session will discuss the scientific and technological cases for future experiments at the PETRA IV storage ring concerning research topics related to "Structure of  nanomaterials and nanoparticles during growth, in-situ and operando conditions”. The input for possible future beamline design parameters and the need for complementary scanning techniques, either for characterization or diagnostics, will emerge from several expert contributions, a poster session and following lively discussions.

Involved Techniques:

X-ray diffraction (XRD), Surface X-ray diffraction (surface XRD), Total scattering, Bragg coherent diffraction imaging (BCDI), Nuclear resonant scattering (NRS), Complementary on- and off-line Scanning Techniques, and more.

Organization:

V. Vonk, T. F. Keller, A. Stierle, F. Bertram, K. Bagschik, F. Westermeier, M. Sprung, M. Etter, I. Sergeev, P. Staron, M. Müller, C. Krywka

3. Quantum Materials: Magnetic, Spin, and Correlated Systems (I & II)

Quantum materials are solids where the quantum nature of the various degrees of freedom leads to special, often spectacular, properties including magnetic order, superconductivity and robust spin-momentum locked transport due to topological symmetries. The recent years have seen the creation of a multitude of devices and switchable materials properties that depend on these phenomena as well as the insight that intrinsic inhomogeneities of the emergent order are quite common, even in chemically homogeneous materials. The interplay and competition between spin, electronic/orbital, charge and lattice degrees of freedom leads to excitation spectra that influence electrical and thermal transport and they can lead to order well beyond the crystalline order of the atomic lattice. X-ray methods to investigate the excitations and the order include polarization-dependent and resonant diffraction techniques, spectroscopy of x-ray absorption as well as the detailed investigation of inelastic excitations such as x-ray fluorescence and photoemission. With advances in x-ray focusing all of these techniques become spatially resolved. The multimodal microscopy is progressively expanded to include specialist diffraction techniques and complex spectroscopies with the ultimate goal of investigating the formation of domains, intrinsic electronic disorder or long range ordering on all length scales. The sessions  "Quantum Materials: Magnetic, Spin, and correlated systems I and II” will discuss the scientific and technological case of materials phenomena and properties that call for detailed investigation using beamlines and instruments on the PETRA IV storage ring. Expert seminars within these sessions will present the visions for instruments to be built on the new storage ring source and their application to the crucial questions of quantum materials research.

Involved Techniques:

High-resolution X-Ray absorption spectroscopy (HR-XAS), X-Ray magnetic circular and linear dichroism (XMCD, XMLD), Photoelectron spectroscopy, Resonant elastic X-Ray scattering (REXS), magnetic X-ray diffraction (XRD), Resonant inelastic X-Ray scattering (RIXS), X-ray resonant magnetic reflectivity (XRMR), Fourier transform holography (FTH), X-ray Raman scattering (XRS), Nuclear resonant scattering (NRS), and more

Organization:

M. Hoesch, C. Schlueter, S. Francoual, H. Gretarsson, D. Novikov, M. Etter, M. v. Zimmermann, K. Rossnagel, M. Beye

4. Thin Films and Nanostructures for Functional Devices - in situ Growth, Coating, and operando Characterization

Modern technologies for thin film growth and coating comprise various advanced vacuum, chemical and solution-based deposition routes. This includes deposition, ALD, CVD as well as advanced printing and scalable fabrication technologies. All of them need to be performed at industrial high-speed conditions. Applied examples are novel memory concepts, magnetic sensors, solar cells, and power electronics. The research aims especially at two routes. On the one hand, this involves performing in situ experiments during growth focusing on the individual growing nanoscale object and its interaction with the surrounding (field, environment, matrix), often in thin film geometry. On the other hand the full device needs to be characterized during operando conditions. Thus tailored instrumentation is needed (multi-source deposition chambers/environments, complementary in situ local analytical and spectroscopic methods) for grazing incidence SAXS & WAXS with nanoscale spatial resolution, including anomalous scattering, HAXPES, PEEM, strain/stress investigations on thin films and nanoobjects, scanning nanodiffraction, full field diffraction microscopy, and operando studies of thin film devices and functional thin films.

Involved Techniques:

Small-angle X-ray scattering (SAXS), Wide-angle X-ray scattering (WAXS), Hard X-ray photoelectron spectroscopy (HAXPES), Anomalous small-angle X-ray scattering (ASAXS), Photoemission electron microscopy (PEEM), X-ray diffraction (XRD), and more

Organization:

F. Bertram, S. Roth, C. Schlueter

5. Fundamental Studies in the Gas Phase: Photo-Induced Reactions of Atoms, Molecules, and Clusters

This session will cover fundamental atomic and molecular processes and the investigation of their intrinsic properties using PETRA IV. Studies on atoms and molecules in the gas phase have covered a breadth of fundamental quantum-mechanical processes in the past, and the development and understanding of novel quantum materials is based on new scientific findings from this discipline. Electron (or in general many-particle) correlation effects, initial state entanglement, molecular structure, and chemical rearrangements are examples of fundamental subjects. The session aims at defining future routes for research in the gas phase employing the enhanced properties of the envisioned PETRA IV storage ring and a P04 successor beam line, including fully variable polarization.

Possible future routes of research could include orbital angular momentum (OAM) / vortex x-ray beams: Manipulating the wave front of a photon field, a phase modulation is created that carries orbital angular momentum in addition to the spin of the photon. The high brightness and lateral coherence of PETRA IV may allow scientists for the first time to generate these novel photon beams at nanometer dimensions and probe unusual electronic transitions; these opportunities will be discussed. Furthermore, the enhanced transverse coherence of the PETRA IV photon beam will enable a further new class of related experiments at the foundation of quantum physics. Using appropriate optics to generate a coherent double focus, tools for novel quantum-technology-inspired few-particle spectroscopy could be developed. For instance, one could extract information from the coherent emission of an electron from two spatially separated sites.

These advanced photon capabilities could be coupled to dedicated novel sources of samples such as well-defined molecular species, individual micro-solvated molecular clusters, single conformers of, e.g., building blocks of life, or enantiomers of dynamically chiral systems. Furthermore, storing ions of temperature-controlled molecules, clusters, single-state small quantum systems and atoms would allow for long-term interrogation, precision measurements, and investigation of their dynamics. These advanced sample environments could enable the investigation of solvation and related transport phenomena, e. g., within the Centre for Molecular Water Science (CMWS), intrinsic biological folding processes and the fundamental working of chirality and its implications for life in general and astrobiology in particular.

Another aspect of the session covers embedded quantum systems for quantum optics. Here, the quantum system is no longer in the gas phase, but placed inside a condensed matter host. The environment of the host, like X-ray cavities or excitations of the host, fundamentally changes the light-matter interaction. New methods of X-ray control via quantum optical concepts can shape the X-ray radiation in energy and time to improve spectroscopic techniques or precision metrology at X-ray energies.

Involved Techniques:

COLTRIMS reaction microscope, Controlled Molecule Imaging, Merged-Beam Technique, Time-of-Flight spectroscopy, Electron beam ion trap (EBIT), high-resolution electron spectroscopy, and more

Organization:

F. Trinter, T. Jahnke, L. Bocklage, S. Trippel, J. Küpper, M. Martins

6. Extreme Pressure & Temperature Research in the Field of Earth Science

In situ studies of Condensed Matter at pressure and temperature conditions found in planetary bodies, such as the Earth, and Warm Dense Matter observed in giant planets are at the forefront of advancing research in the field of natural sciences. Samples are illuminated with high-energy synchrotron X-ray beams in diamond anvil cells (DAC), large volume presses (LVP) and dynamic Laser-driven shock devices to investigate their structure, physical properties and kinetics of transformational processes using X-ray diffraction, spectroscopy and imaging techniques. Current techniques used at PETRA III will be enhanced and new techniques added, such as time-resolved microtomography, phase contrast, coherent Bragg diffraction imaging, ptychography, and synchrotron Mössbauer spectroscopy. PETRA IV will break new ground by enabling the study of Earth materials at length and time scales of several orders of magnitude such as probing micron-sized crystallites in a larger bulk rock experiencing different pressure, temperature and stress states. Using the LVP, grain boundary structures and processes, which play a critical role in mantle dynamics and melt transport, can be resolved. Using the DAC, meteorite impacts can be simulated and tiny samples at pressures present in giant planets can be investigated. These studies will all be enabled through PETRA IV that delivers a small round (focused) beam at high energies (>14 keV to 100 keV), combined with its high coherence, and most importantly as a consequence of the highest brilliance at high energies compared to other DLSR.

Involved Techniques:

X-ray diffraction (focused and unfocused, on powders and single crystals), Scattering on amorphous and liquid materials, Absorption Contrast Imaging (Radiography), Phase Contrast Imaging, Time-resolved Micro-tomography, Near-field and Far-field High Energy Diffraction Microscopy, Coherent Bragg Diffraction Microscopy, Scanning transmission X-ray Microscopy, Spectroscopy (XES, XANES, EXAFS, RAMAN, fluorescence, etc.) and X-ray diffraction, Ptychography, Nuclear forward scattering, Nuclear Inelastic Scattering, Synchrotron Mössbauer source, and more

Organization:

H. P. Liermann, R. Farla, K. Glazyrin, I. Sergeev

7. Non-destructive Analysis of Environmental, Geochemical, and Cultural Heritage Samples under Ambient Conditions

Many samples require non-destructive analytical methods, either because destructive methods would change the sample composition and thus compromise the analytical results or because the nature of the object under investigation does not allow to apply any method that causes lasting damage. An example for the first is the determination of the chemical binding forms of elements in environmental or geochemical samples, an example for the latter the analysis of chemical binding forms and/or composition in objects from cultural heritage like the pigments in paintings. X-ray spectroscopic methods are an indispensable analytical tool in these fields of science. Many of these investigations require nm-sized focused beams with high photon flux in order to  achieve a high spatial resolution and low detection limits. PETRA IV will offer unique beam properties that will be helpful in achieving the desired parameters. The high coherent flux and small focus sizes will dramatically improve the spatial resolution. Hence, high resolution investigations can be performed routinely. Technically less demanding are experiments on sample systems that require a larger beam to investigate their bulk properties, like for instance the binding form of elements in soils or other environmental samples. While this type of experiments will not especially profit from PETRA IV beam properties they will still be possible and examples for both types of investigations will be presented and discussed in this session.

Involved Techniques:

X-ray absorption spectroscopy (XAS), X-ray fluorescence (XRF), micro- and nano-Imaging, and more

Organization:

E. Welter, G. Falkenberg

8. Glasses and Amorphous Solids

The glass transition is a dynamical phenomenon where a liquid freezes to a metastable solid by either cooling or compression.  Modern, high technology glasses enable worldwide communication by the glass fiber network.  Glasses collect or disperse light, act as storages or converters, are sensors, substrates or protectors as well as simple windows or high-end intelligent house envelops.  Glasses and amorphous materials are at the forefront of global research activities.  On the one side the fundamental nature of the glass transition on the microscopic level as a function of temperature and pressure is an open scientific question and widely studied in basic research.  On the other side the unique mechanical properties of (metallic) glasses like hardness, toughness and resilience are of utmost interest in material science.  In addition, inorganic glasses are attracting interest to make extraordinary thin, bend or scaffold glasses mechanically stronger and more flexible for future applications in telecommunication, automotive and transport applications.

The unique properties of PETRA IV will enable investigations of glasses and other amorphous solids by classical as well as coherent X-ray scattering techniques with unprecedented resolutions in both time and spatial domains.  Total scattering methods at PETRA IV will significantly improve due to its low divergence combined with state of the art undulator sources.  The possibility to focus the large coherent fraction of PETRA IV efficiently into nanometer sized spots allows probing the inhomogeneous structure of these materials on a locally relevant level thus overcoming assembly averaging processes typically applied. X-ray cross correlation analysis (XCCA) methods can reveal dominant or even multiple near-neighbor configurations to help gaining a deeper understanding of the glass or jamming transition phenomena. X-ray photon correlation spectroscopy (XPCS) techniques are expected to profit to the largest extent from the upgrade to PETRA IV.  XPCS will probe dynamical processes of a broad range of systems, ranging from soft matter to metallic and inorganic network glasses. Dynamics of supercooled liquids approaching the glass transition can be probed on relevant length scales covering time scales from (sub-) microseconds to the deep glassy regime.  For the first time, the excellent coherent properties of PETRA IV at high X-ray energies allow XCCA and XPCS studies of these materials under extreme conditions.

Involved Techniques:

X-ray cross-correlation analysis (XCCA), X-ray photon correlation spectroscopy (XPCS), and more

Organization:

M. Sprung, F. Westermeier, F. Lehmkühler, K. Glazyrin

9. CMWS Research in Molecular Physics, Astrochemistry, and Atmospheric Science

The Centre for Molecular Water Science (CMWS) brings together key experts from different areas of water-related sciences with the common goal of achieving a detailed molecular understanding of water. This includes the dynamic processes in bulk water and at water interfaces, which are highly relevant for chemistry, biology, earth science, and the environment as well as for technology. The scope of the CMWS will range from studies of the fundamental properties of water to its role in real-time chemical dynamics, biochemical and biological reactions. It will equally cover questions in geo- and astroscience, environmental and climate research and address the need for water-based energy technologies. The CMWS research agenda will generate the necessity for new experimental capabilities and will in particular benefit from future light sources such as PETRA IV. This session will address structure and dynamics of water in the wide area of molecular physics, covering experiments on liquid water, aqueous solutions, individual water molecules and clusters of water with itself or with other molecules. The latter are particularly relevant for astrophysics and atmospherically relevant studies, such as aerosol formation. For all of these topics, source development is also of high priority.

Involved Techniques:

Liquid-jet photoelectron spectroscopy, Liquid-jet photoelectron circular dichroism, COLTRIMS reaction microscope, Merged-Beam Technique, Time-of-Flight spectroscopy, Water-interface studies, molecular beams and liquid jets, flat jets, aerosol sources, and more

Organization:

M. Schnell, F. Trinter, U. Hergenhahn