Stefano Marchesini
A5079976946- Advanced X-ray Imaging Techniques
- Advanced Electron Microscopy Techniques and Applications
- Crystallography and Radiation Phenomena
- X-ray Spectroscopy and Fluorescence Analysis
- Medical Imaging Techniques and Applications
- Laser-Plasma Interactions and Diagnostics
- Enzyme Structure and Function
- Particle Accelerators and Free-Electron Lasers
- Optical measurement and interference techniques
- Advanced X-ray and CT Imaging
- X-ray Diffraction in Crystallography
- Electron and X-Ray Spectroscopy Techniques
- Digital Holography and Microscopy
- Astrophysical Phenomena and Observations
- Photosynthetic Processes and Mechanisms
- Laser Material Processing Techniques
- Magnetic properties of thin films
- High-pressure geophysics and materials
- Advanced Measurement and Metrology Techniques
- nanoparticles nucleation surface interactions
- Nuclear Physics and Applications
- Nuclear materials and radiation effects
- Electronic and Structural Properties of Oxides
- Magnetic and transport properties of perovskites and related materials
- Quantum, superfluid, helium dynamics
SLAC National Accelerator Laboratory
2005-2024
Lawrence Berkeley National Laboratory
2013-2022
Alive Hospice
2020
Sigray (United States)
2020
Tianjin Normal University
2018
Research Applications (United States)
2016
University of California, Davis
2007-2014
Advanced Light Source
2014
Max Planck Institute for Medical Research
2011
Deutsches Elektronen-Synchrotron DESY
2011
A solution to the inversion problem of scattering would offer aberration-free diffraction-limited three-dimensional images without resolution and depth-of-field limitations lens-based tomographic systems. Powerful algorithms are increasingly being used act as lenses form such images. Current image reconstruction methods, however, require knowledge shape object low spatial frequencies unavoidably lost in experiments. Diffractive imaging has thus previously been increase obtained by other...
Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate with high resolution all three dimensions, as determined quantitative analysis reconstructed volume images. These images are retrieved from three-dimensional data using no priori knowledge about shape or composition object, which has never before been demonstrated on object. also construct...
Iterative projection algorithms are successfully being used as a substitute of lenses to recombine, numerically rather than optically, light scattered by illuminated objects. Images obtained computationally allow aberration-free diffraction-limited imaging and the possibility using radiation for which no exist. The challenge this technique is transferred from algorithms. We evaluate these new computational “instruments” developed phase-retrieval problem, discuss acceleration strategies.
We demonstrate the use of an X-ray free electron laser synchronized with optical pump to obtain diffraction snapshots from photoactivated states large membrane protein complexes in form nanocrystals flowing a liquid jet.Light-induced changes Photosystem I-Ferredoxin co-crystals were observed at time delays 5 10 µs after excitation.The result correlates microsecond kinetics transfer I ferredoxin.The undocking process that follows leads rearrangements crystals will terminally lead...
Helium nanodroplets are considered ideal model systems to explore quantum hydrodynamics in self-contained, isolated superfluids. However, exploring the dynamic properties of individual droplets is experimentally challenging. In this work, we used single-shot femtosecond x-ray coherent diffractive imaging investigate rotation single, superfluid helium-4 containing ~10(8) 10(11) atoms. The formation vortex lattices inside confirmed by observing characteristic Bragg patterns from xenon clusters...
Intense femtosecond x-ray pulses from free-electron laser sources allow the imaging of individual particles in a single shot. Early experiments at Linac Coherent Light Source (LCLS) have led to rapid progress field and, so far, coherent diffractive images been recorded biological specimens, aerosols, and quantum systems with few-tens-of-nanometers resolution. In March 2014, LCLS held workshop discuss scientific technical challenges for reaching ultimate goal atomic resolution single-shot...
In nanotechnology, strategies for the creation and manipulation of nanoparticles in gas phase are critically important surface modification substrate-free characterization. Recent coherent diffractive imaging with intense femtosecond X-ray pulses has verified capability single-shot nanoscale objects at suboptical resolutions beyond radiation-induced damage threshold. By intercepting electrospray-generated particles a single 15 soft-X-ray pulse, we demonstrate specimen free flight first time,...
In this paper, we show how the augmented Lagrangian alternating direction method (ADM) can be used to solve both classical and ptychographic phase retrieval problems. We point out connection between ADM projection algorithms such as hybrid input–output algorithm, compare its performance against standard for on a number of test images. Our computational experiments that appears less sensitive choice relaxation parameters, it usually outperforms existing techniques
X-ray free-electron lasers deliver intense femtosecond pulses that promise to yield high resolution diffraction data of nanocrystals before the destruction sample by radiation damage. Diffraction intensities lysozyme collected at Linac Coherent Light Source using 2 keV photons were used for structure determination molecular replacement and analyzed damage as a function pulse length fluence. Signatures are observed short 70 fs. Parametric scaling in conventional crystallography does not...
We report the first image of an intact, frozen hydrated eukaryotic cell using x-ray diffraction microscopy, or coherent imaging. By plunge freezing specimen in liquid ethane and maintaining it below $\ensuremath{-}170\text{ }\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$, artifacts due to dehydration, ice crystallization, radiation damage are greatly reduced. In this example, data 520 eV x rays were recorded reconstructed reveal a budding yeast at resolution better than 25 nm. This...
Abstract Battery function is determined by the efficiency and reversibility of electrochemical phase transformations at solid electrodes. The microscopic tools available to study chemical states matter with required spatial resolution specificity are intrinsically limited when studying complex architectures their reliance on two-dimensional projections thick material. Here, we report development soft X-ray ptychographic tomography, which resolves in three dimensions 11 nm resolution. We an...
Xi-cam is an extensible platform for data management, analysis and visualization. aims to provide a flexible approach synchrotron treatment as solution rising demands high-volume/high-throughput processing pipelines. The core of plugin-based graphical user interface which provides users with interactive algorithms. Plugins are available SAXS/WAXS/GISAXS/GIWAXS, tomography NEXAFS data. With Xi-cam's `advanced' mode, steps designed graph-based workflow, can be executed live, locally or...
The performance of battery electrode materials is strongly affected by inefficiencies in utilization kinetics and cycle life as well size effects. Observations phase transformations these with high chemical spatial resolution can elucidate the relationship between processes mechanical degradation. Soft X-ray ptychographic microscopy combined absorption spectroscopy electron creates a powerful suite tools that we use to assess morphological changes lithium iron phosphate (LiFePO4) micro-...