To reconstruct the object, the Fourier phase has to be retrieved from this diffraction pattern alone. Such ‘diffraction before destruction’ methods 8, 9, 10, 11 are inherently restricted to a single diffraction pattern from every object. These pulses are bright enough to scatter a considerable amount of light from a single molecule, and fast enough to do it long before it starts to dissociate. Recent progress in X-ray sources such as X-ray free-electron lasers (XFELs) has provided ultra-bright X-ray pulses, which are as short as few femtoseconds. Specifically, an extremely promising application is ‘diffraction before destruction’ experiments. Since suitable lenses are not available at the very-short-wavelength (X-ray) regime, retrieval of the Fourier phase is of crucial importance. The fundamental bound on resolution-the diffraction limit-implies that imaging from a distance with subnanometric resolution requires short-wavelength sources. An important branch of applications is high-resolution imaging, the importance of which to physics, material science and biology cannot be overestimated. It has found numerous applications spanning from nature’s smallest scales to the largest: from quantum physics 4, material science 5 and biology 6, to communications and astronomy 7. Reconstructing the phase of a field from intensity measurements is an old and ubiquitous challenge, known as the phase retrieval problem 1, 2, 3. Our scheme alleviates several limitations of current methods, offering a new pathway towards direct reconstruction of complex objects. We establish our method numerically and experimentally in the optical domain and demonstrate a proof-of-principle single-shot coherent diffractive imaging using X-ray free-electron lasers pulses. In our approach, the objects serve as unknown references to one another, reducing the phase problem to a solvable set of linear equations. Here we present a convex scheme for single-shot phase retrieval for two (or more) sufficiently separated objects, demonstrated in two dimensions. Presently, the phase is reconstructed by iterative algorithms, imposing a non-convex computational challenge, or by Fourier holography, requiring a well-characterized reference field. Recent advances in X-ray free-electron lasers allow capturing of the diffraction pattern from a single nanoparticle before it disintegrates, in so-called ‘diffraction before destruction’ experiments. An important application is coherent diffractive imaging. Raman spectroscopic studies elucidated the behavior of the substance and the relation among phases of tetra-arsenic tetrasulfide.The non-crystallographic phase problem arises in numerous scientific and technological fields. They were characterized using powder and single crystal X-ray diffraction techniques to confirm the phase identification and the lattice parameters. The grown crystals are as large as 0.50×0.50×0.01 mm. The crystal exhibits a platelet-like shape as a thin film with well-developed faces (0 1 0) and (0 1¯ 0). Single crystals of As 4S 4 (II) obtained using this method were translucent and showed a uniform yellow-orange color. Results show that single crystals of the As 4S 4 (II) phase were obtained reproducibly through the dissolution–recrystallization process. Then it is dissolved and recrystallized from CS 2 solvent. First, through photo-induced phase transformation, pararealgar powder is prepared as a precursor instead of AsS melt. As described by Kutoglu (1976 ), single crystals of As 4S 4 (II) phase have been grown using a new two-step synthesis that drastically increases the reproducibility that is attainable in synthetic experiments.
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