Fresnel Coherent Diffractive Imaging from Periodic Samples

s: Imaging 1 of 66 Femtosecond pump-probe coherent X-ray diffraction imaging of ultra-fast processes Henry N. Chapman, Anton Barty, Stefano Marchesini, Sebastien Boutet, Michael J. Bogan, Stefan P. Hau-Riege, Matthias Frank, Bruce W. Woods, Saša Bajt, J. Hajdu, M. Marvin Seibert, Marion Kuhlmann and Rolf Treusch 1 University of California, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550, USA. 2 Center for Biophotonics Science and Technology, University of California, Davis, 2700 Stockton Blvd., Suite 1400, Sacramento, CA 95817, USA. 3 Stanford Synchrotron Radiation Laboratory, Stanford Linear Accelerator Center, 2575 Sand Hill Road, Menlo Park, California 94305, USA. 4 Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, SE-75124 Uppsala, Sweden. 5 Institut für Atomare Physik, Technische Universität Berlin, Hardenbergstraße 36, PN 3-1, 10623 Berlin, Germany. 5 Deutsches Elektronen-Synchrotron, DESY, Notkestraße 85, D-22607 Hamburg, Germany. The intense, ultra-fast X-ray pulses produced by free electron lasers offer unique opportunities to study the dynamics of complex transient phenomena in materials. In particular, the high spatial coherence of these sources permit the use of coherent diffraction imaging to produce snapshots of the evolution of fast dynamic processes through time. The short wavelength of X-ray radiation allows probing the evolution of processes throughout the bulk of a sample, at spatial resolutions from the nanometer scale using current sources through to inter-atomic length scales using future hard X-ray FEL sources. In the X-ray regime, time-resolved pump-probe experimental methods are challenging, requiring complex X-ray optical systems and diagnostics to synchronise the X-ray pulses that initiate a process and then probe it at a precisely defined time delay. We have developed and demonstrated a simple holographic technique in which the same X-ray pulse both pumps and probes the sample. The sample is placed near an Xray mirror, which reflects the pulse back on to the sample after it initiates (or pumps) the reaction. The time delay is encoded by mirror separation to an accuracy of 1 fs, the sample structure is holographically recorded to sub-wavelength accuracy, and analysis of holograms recorded at different time delays yields information on the sample evolution through time. We have applied the technique to measure the explosion of hydrocarbon particles and other samples in intense FEL pulses. We observe sample explosion occurring well after initial sample heating, supporting the notion that X-ray flash imaging can be used to achieve high resolution beyond radiation damage limits for biological and other samples. Abstracts: Imaging 2 of 66s: Imaging 2 of 66 Shotgun Femtosecond Diffractive Imaging of Free Nanoscale Biomaterials Michael J. Bogan, Urs Rohner, Sébastien Boutet, W. Henry Benner, Anton Barty, Saša Bajt, Matthias Frank, Bruce Woods, Stefano Marchesini, Stefan P. Hau-Riege, Marvin Seibert, Filipe Maia, Florian Burmeister, Erik Marklund, Rolf Treusch, Eberhard Spiller, Thomas Möller, Christoph Bostedt, Janos Hajdu, and Henry N. Chapman 1. University of California, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550, USA. 2. Stanford Synchrotron Radiation Laboratory, Stanford Linear Accelerator Center, 2575 Sand Hill Road, Menlo Park, California 94305, USA. 3. Laboratory of Molecular Biophysics, Institute of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, S-75124 Uppsala, Sweden 4. Center for Biophotonics Science and Technology, University of California, Davis, 2700 Stockton Blvd., Suite 1400, Sacramento, CA 95817, USA. 5. Deutsches Elektronen-Synchrotron, DESY, Notkestraße 85, D-22607 Hamburg, Germany 6. Spiller X-ray Optics, Livermore CA 94550, USA. 7. Institut für Atomare Physik, Technische Universität Berlin, Hardenbergstraße 36, PN 3-1, 10623 Berlin, Germany Femtosecond diffractive imaging is a new x-ray microscopy technique for imaging noncrystalline objects beyond the damage threshold. Part of a new era of X-ray science delivered by X-ray free electron lasers (FEL), this technique has the potential to deliver three-dimensional atomic resolution structures of non-crystalline nanoscale biomaterials such as single biomolecules using images collected from reproducible copies exposed to the beam one by one. Experimentally, container-less delivery of single biomolecules to the X-ray pulses is imperative because any atom present in the X-ray path will contribute to the diffraction pattern. Here we use the soft-X-ray FEL in Hamburg (FLASH) to perform the first demonstration femtosecond diffractive imaging of free nanoscale biomaterials via a shotgun approach-a continuously refreshed stream of single nanoparticles synthesized in situ at atmospheric pressure by charge-reduced electrospray of a sucrose solution containing megadalton DNA origami complexes. In our method, the aerosol is transformed into a tightly focused particle stream in-vacuum using a set of aerodynamic lenses and single events of the interception of individual nanoparticles with an intense 10 femtosecond pulse, containing ~10 photons at 13.5 nm, results in a coherent diffraction pattern captured with a single photon sensitive X-ray camera. Reconstructed images of intercepted particles are obtained by phase retrieval through oversampling. Ions generated from the explosion of the nanoparticle are detected by a miniature mass spectrometer, providing insights to chemical composition. In its current configuration shotgun femtosecond diffractive imaging operates at 0.1 Hz and is directly transferable to future hard-X-ray FEL sources. Abstracts: Imaging 3 of 66s: Imaging 3 of 66 Iterative phase retrieval in one dimension for studying confinement induced ordering in microfluidic arrays Oliver Bunk, Franz Pfeiffer, Ana Diaz, Christian David, Bernd Schmitt, Dillip K. Satapathy, and J. F. van der Veen Research Department Synchrotron Radiation and Nanotechnology, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland, Present address: European Synchrotron Radiation Facility, BP220, 38043 Grenoble Cedex, France, ETH Zurich, 8093 Zürich, Switzerland Arrays of microfluidic channels lend themselves, e.g., to studying confinement induced ordering in model liquids or as orienting template for macromolecular small angle x-ray scattering (SAXS) studies in transmission geometry. We report on the microfluidic array phase profiling (MAPP) technique, focusing on iterative retrieval of one-dimensional complex-valued exit fields, and its application to studies of confinement induced ordering in model fluids. The technique has several advantages. In contrast to traditional lensless imaging fully coherent illumination is not required. The ensemble averaged structure rather than individual realizations are investigated and thereby the dose on the specimen is reduced by orders of magnitude. By statistical averaging of solutions we show that the resolution is currently in the 10 nm range.