A5081182046- Advanced X-ray Imaging Techniques
- Advanced Electron Microscopy Techniques and Applications
- Magnetic properties of thin films
- Particle Accelerators and Free-Electron Lasers
- Quantum Dots Synthesis And Properties
- Crystallography and Radiation Phenomena
- Pickering emulsions and particle stabilization
- Gold and Silver Nanoparticles Synthesis and Applications
- Advanced MRI Techniques and Applications
- Microfluidic and Capillary Electrophoresis Applications
- Innovative Microfluidic and Catalytic Techniques Innovation
- X-ray Spectroscopy and Fluorescence Analysis
- Quantum and electron transport phenomena
- Terahertz technology and applications
- Material Dynamics and Properties
- Phase Equilibria and Thermodynamics
- Particle physics theoretical and experimental studies
- Plant Water Relations and Carbon Dynamics
- Fluid Dynamics and Turbulent Flows
- Magnetic Properties of Alloys
- Seismic Imaging and Inversion Techniques
- Geological and Geochemical Analysis
- Optical Coatings and Gratings
- Geomagnetism and Paleomagnetism Studies
- Laser-Plasma Interactions and Diagnostics
Deutsches Elektronen-Synchrotron DESY
2012-2024
Max Planck Institute for the Structure and Dynamics of Matter
2020
Hamburg Centre for Ultrafast Imaging
2020
One of the important challenges in condensed matter science is to understand ultrafast, atomic-scale fluctuations that dictate dynamic processes equilibrium and non-equilibrium materials. Here, we report an step towards reaching goal by using a state-of-the-art perfect crystal based split-and-delay system, capable splitting individual X-ray pulses introducing femtosecond nanosecond time delays. We show results ultrafast hard photon correlation spectroscopy experiment at LCLS where split were...
Dynamics and kinetics in soft matter physics, biology, nanoscience frequently occur on fast (sub)microsecond but not ultrafast timescales which are difficult to probe experimentally. The European X-ray Free-Electron Laser (European XFEL), a megahertz hard source, enables such experiments via taking series of diffraction patterns at repetition rates up 4.5 MHz. Here, we demonstrate photon correlation spectroscopy (XPCS) with submicrosecond time resolution samples the XFEL. We show that XFEL...
New stable states of liquid crystal 8CB could be induced by nonlinear shear conditions and observed a newly developed rheology/X-ray scattering setup using synchrotron X-ray radiation. Nonlinear oscillatory created distorted sixth order orientational structure. Even when is switched off, the structure remains can removed only heating system into isotropic state. We assume to stabilized defects that pin new 6-fold phase.
Self-assembled nanocrystal superlattices have attracted large scientific attention due to their potential technological applications. However, the nucleation and growth mechanisms of superlattice assemblies remain largely unresolved experimental difficulties monitor intermediate states. Here, self-assembly colloidal PbS nanocrystals is studied in real time by a combination controlled solvent evaporation from bulk solution situ small-angle X-ray scattering (SAXS) transmission geometry. For...
Many soft-matter systems are composed of macromolecules or nanoparticles suspended in water. The characteristic times at intrinsic length scales a few nanometres fall therefore the microsecond and sub-microsecond time regimes. With development free-electron lasers (FELs) fourth-generation synchrotron light-sources, time-resolved experiments such ranges will become routinely accessible near future. In present work we report our findings on prototypical systems, charge-stabilized silica...
The controlled manipulation of spins on ultrashort timescales is among the most promising solutions for novel high-speed and low-power-consumption spintronic magnetic recording applications. To do so, terahertz (THz) light pulses can be used to drive coherent magnetization dynamics in ferromagnetic thin films. We were able resolve these nanoscale employing THz-pump x-ray resonant scattering from labyrinth-type domain network a Co/Pt multilayer with perpendicular anisotropy. Our results...
A hard X-ray delay line device capable of splitting single FEL pulses into two adjustable fractions and recombining them with the goal performing Photon Correlation Spectroscopy pump - probe type studies was designed. The performance has been verified at XPP XCS instruments LCLS. measured throughput 7.9 keV is 3.6%. coherence properties LCLS beam passing through were investigated by analyzing speckle patterns produced pulses. high contrast 0.69 found, indicating feasibility based experiments line.
We study the in situ self-assembly of faceted PbS nanocrystals from colloidal suspensions upon controlled solvent evaporation using time-resolved small-angle X-ray scattering and cross-correlation analysis. In our bulk-sensitive experiment transmission geometry, superlattice crystallization is observed real time, revealing a hexagonal closed-packed (hcp) structure followed by formation body-centered cubic (bcc) superlattice. The bcc undergoes continuous tetragonal distortion solvated state...
In this paper we describe a setup for x-ray scattering experiments on complex fluids using liquid jet. The supports Small and Wide Angle X-ray Scattering (SAXS/WAXS) geometries. jet is formed by gas-dynamic virtual nozzle (GDVN) allowing diameters ranging between 1 μm 20 at length of several hundred μm. To control properties such as length, diameter, or flow rate, the instrument equipped with diagnostic tools. Three microscopes are installed to quantify dimensions stability in situ. has been...
A compact hard X-ray split-and-delay line for studying ultrafast dynamics at free-electron laser sources is presented. The device capable of splitting a single pulse into two fractions to introduce time delays from -5 815 ps with femtosecond resolution. can operate in wide and continuous energy range between 7 16 keV. Compact dimensions 60 × 30 cm total weight about kg make it portable suitable direct installation an experimental hutch. concept the based on crystal diffraction. piezo-driven...
During the self-organization of colloidal semiconductor nanoparticles by solvent evaporation, nanoparticle interactions are substantially determined organic ligands covering inorganic core. However, influence ligand grafting density on assembly pathway is often not considered in experiments. Here, we carry out an situ synchrotron small-angle X-ray scattering and cross-correlation analysis study real-time oleic acid-capped PbS nanocrystals at a low coverage 2.7 molecules/nm2. With high...
Abstract The ability to deliver two coherent X-ray pulses with precise time-delays ranging from a few femtoseconds nanoseconds enables critical capabilities of probing ultra-fast phenomena in condensed matter systems at free electron laser (FEL) sources. Recent progress made the hard split-and-delay optics developments now brings very promising prospect for resolving atomic-scale motions that were not accessible by previous time-resolved techniques. Here, we report on characterizing spatial...
We present a sample environment for the investigation of nanoparticle self-assembly from colloidal solution via controlled solvent evaporation using in situ small-angle X-ray scattering. Nanoparticles form ordered superlattices evaporative assembly along transparent windows three-dimensional cell. The special design cell allows monitoring superlattice formation and transformation at different stages process during movement front real time. presented can be used to study self-organization...
We applied shear to a silica nanoparticle dispersion in microfluidic jet device and observed direction-dependent structure along across the flow direction. The asymmetries of diffraction patterns were evaluated by x-ray cross correlation analysis. For different Rayleigh nozzle sizes shapes, we measured decay shear-induced ordering after cessation shear. At large tube small rates, characteristic times become longer, but Péclet-weighted do not scale linearly with Péclet numbers. By modeling...
Abstract The availability of sub 100 fs short and highly intense free-electron laser (FEL) pulses allows for new insights in laser-induced ultrafast demagnetization (LID) ferromagnetic thin films on nanometer length scales. We designed a pair in-vacuum Helmholtz coils, providing pulsed magnetic fields up to µ 0 H z = ±45 mT, time-resolved experiments at FEL sources transmission geometry. report the implementation coils an optical-pump–resonant-magnetic-scattering (tr-XRMS) experiment FERMI...
A transmission polarizer for producing elliptically polarized soft X-ray radiation from linearly light is presented. The setup intended use at synchrotron and free-electron laser beamlines that do not directly offer circularly for, e.g., magnetic circular dichroism (XMCD) measurements or holographic imaging. Here, we investigate the degree of ellipticity upon through a cobalt thin film. experiment was performed photon energy resonant to Co L3-edge, i.e., 778 eV, polarization transmitted...
Abstract We report on the feasibility of Fourier transform holography in hard X-ray regime using a Free Electron Laser source. Our study shows successful single and multi-pulse holographic reconstructions nanostructures. observe beam-induced heating sample exposed to intense pulses leading reduced visibility reconstructions. Furthermore, we extended our exploring recording with split-and-delay optics. paves way towards studying dynamics at sub-nanosecond timescales atomic lengthscales.
We present a novel experimental setup for performing precise pre-alignment of hard X-ray split-and-delay unit based on low coherence light interferometry and high-precision penta-prisms. A is sophisticated perfect crystal-optics device that splits an incoming pulse into two sub-pulses generates controlled time-delay between them. While the availability system will make ultrafast time-correlation pump-probe experiments possible at free-electron lasers, its alignment process can be very...
An endstation for pump–probe small-angle X-ray scattering (SAXS) experiments at the free-electron laser in Hamburg (FLASH) is presented. The houses a solid-state absorber, optical incoupling experiments, time zero measurement, sample chamber, and detection unit. It can be used all FLASH beamlines whole photon energy range offered by FLASH. capabilities of setup are demonstrated showing results resonant magnetic SAXS measurements on cobalt-platinum multilayer samples grown freestanding $\rm...
Three-dimensional photon correlation spectroscopy (3D PCS) is a well-known technique developed to suppress multiple scattering contributions in functions, which are inevitably involved when an optical laser employed investigate dynamics turbid system. Here, we demonstrate proof-of-principle study of 3D PCS the hard X-ray regime. We employ cross-correlator measure silica colloidal nanoparticles dispersed polypropylene glycol. The obtained cross functions show very good agreement with...
Abstract Free-electron lasers (FELs) provide unique possibilities in investigating matter down to femtosecond time and nanometer length scales, as well the regime of non-linear light-matter interaction. Due nature FEL sources, produced beam is significantly more unstable than beams by 3 rd generation synchrotrons. As a result, pulse-resolved normalization measurement data becomes essential can be challenging. The intensity monitors permanently installed at facility might indeed accurately...
Abstract We report on a Fourier transform holography study, employing hard X-ray energies at 3rd generation storage ring. Nano-structures of various sizes and shapes have been measured in ultra small angle x-ray scattering configuration reaching resolution the holographic reconstructions about 50 nm. Reliable holograms obtained with 6.9×10 6 incident photons. Our results provide an important step forward towards routine split-pulse measurements FEL sources 4th ultralow-emittance sources.