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Showing 1 to 20 of 33 for “"reciprocal space"”.
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Reciprocal space phase gradient neutron imaging
Perfect crystal real space imaging has limitations in its resolution imposed by position sensitive detectors. The disadvantage, its limited resolution, of a position-sensitive detector can be overcome by replacing the conventional detector with an area detector and moving to reciprocal space. …
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Travel Writing, Self and Other: Finding Reciprocal Space
… of terms – indicate that seeking out such reciprocal engagements in these authors’ travel writings is a fruitful expansion in the field of travel writing studies.
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Low Resolution ab initio Phasing Method by Modification of Density and Phase in Real and Reciprocal Space
… masks are generated and modified alternately in reciprocal and real space. Then, the output phase sets are averaged to give the estimated phases and figure of merit which are capable of capturing key feature of the molecules’ low resolution envelope by Fourier synthesis. Smoothed particle …
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Optimization Techniques for Phase Retrieval Based on Single-Crystal X-Ray Diffraction Data
… CRUNCH for a variety of test structures. Next a reciprocal space integer minimal principle model and polynomial-time Sieve method are developed. The Sieve method is shown to phase one order-of-magnitude faster on average than SnB for a variety of test structures. A shift in emphasis to direct …
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Coherent X -Ray Diffraction
… Cu 3Au is described, along with the associated reciprocal-space structure which is measured by CXD. CXD measurements place relatively stringent requirements on the coherence properties of the beam and on the detection mechanism of the experiment; these requirements and the means by which they …
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Coherent control of neutron interferometry
… In particular we introduce methods for reciprocal space encoding of spatial information systematically in a neutron interferometer. First, a proof of principle experiment is conducted for coherent reciprocal space neutron imaging. This newly proposed technique overcomes the limitation of …
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Structural, Magnetic, Dielectric, and Optical Properties of DyCrO3 and GeNi2O4 Materials
… as an X-ray diffraction, X-ray reflectivity, reciprocal space mapping, and in-plane pole figures. The results were analyzed to determine the preferred orientation, the thickness of the thin films, the presence of strain and defects, and the degree of epitaxy. The reciprocal space mapping …
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Computational Analysis of Silicon Nanoelectromechanical Systems
… temperature. Three models, namely the real space quasiharmonic (QHM) model, the local quasiharmonic (LQHM) model, and the reciprocal space quasiharmonic (QHMK) model are investigated. Within this framework, we compute the effect of the temperature and strain on mechanical properties of …
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Ultrafast lattice dynamics in photoexcited nanostructures : femtosecond X-ray diffraction with optimized evaluation schemes
… resolution. The implementation of a high-speed reciprocal-space mapping technique allowed for a two-dimensional structural analysis with femtosecond temporal resolution. I have studied the ultrafast lattice dynamics, namely the excitation and propagation of coherent phonons, in photoexcited thin …
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Growth of Single Crystal, Metastable Ge(1-X)sn(x) Alloys and Ge(1-X)sn(x)/ge Strained-Layer Superlattices on Ge(001)2 X 1 by Molecular Beam Epitaxy
… Ge\sb{1-x}Sn\sb{x}(001)2x1$ alloy and Ge(001)2x1 spacer layers were commensurate. In fact, the alloy layers were essentially fully strained with an average in-plane lattice constant mismatch of $(1\pm2)\times10\sp{-5}$ and an average tetragonal strain in the growth direction of …
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Assessing electronic transport in solid materials via the fluctuation-dissipation theorem
… materials typically require both dense reciprocal-space 𝐤-grids for the electronic degrees of freedom and large real-space supercells for the vibrational ones. This is especially challenging for the charge transport coefficient of intrinsic semiconductors with dispersive electronic …
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Three-dimensional nanostructure determination based on scanning electron nanodiffraction
… (SEND) to acquire diffraction patterns in the 3D reciprocal space, with the help of a special sample holder for large angle rotation. Grains are identified in the 3D real space based on the crystal orientation and the reconstructed dark-field images from the recorded diffraction patterns. Various …
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Stress relaxation of AZ31 alloy using high energy diffraction microscopy
… peak isolation, trajectory generation, reciprocal space--detector space transformation, ellipse fitting and peak strain--orientation correlation.
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The Use of Synchrotron Radiation to study Overgrowth Phenomena in InAs/GaAs Nanostructures
… The evaluation of intensity mappings recorded in reciprocal space close to the (200) reflection together with atomic force micrographs (AFM) allows to attribute the strain and the InAs concentration to a certain height in the quantum dots. Thereby, a three-dimensional model of the strain and …
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Synchrotron radiation-based characterization of GaN- based MQW structures and strongly correlated materials
… based HRXRD and in particular cross-sectional reciprocal space mapping (RSM) was then extended to studying the intriguing structural properties of a ZnMnGaO_4 film epitaxially grown on MgO (001) substrate. The results of this study helped in identifying the ZnMnGaO_4 film, as consisting of a …
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Structure Solution Using Precession Electron Diffraction and Diffraction Tomography
… of diffraction maxima into three-dimensional reciprocal space following an automated peak detection process. The factors which complicate the process of unit cell determination are discussed, and an algorithm designed for autoindexing “obstinate” lists of X-ray reflections was found to be able …
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Static and dynamic correlation in lattice gas systems : an application to the intermetallic hydride ZrV2Hx
… quasielastic line-width is reduced atpoints in reciprocal space corresponding to maxima in SdiflGRT is subsequently applied to the intermetallic hydride (deuteride) ZrV 2 H(D) x . Theform of G(r) with repulsive interactions is simulated as a function of concentration.This is compared to G(r), …
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Variable Temperature Scanning Tunneling Microscopy Study of a High Temperature Superconductor Bi2Sr2CaCu2O8+d
… characterize electronic states both in real and reciprocal space. These techniques allow us to analyze our data in the context of many theoretical and experimental results and approaches. Our results confirm many aspects of prior observations at low temperatures. Specifically, our data at 40 K …
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Self-organization in Models of Cyclically Sheared Suspensions
… characterize the spatial structure in both real space and reciprocal space to bolster our findings. In Chapter 3, we were inspired by dynamical jamming fronts [1], which prompted us to conduct a detailed study of our sheared suspension system with sedimentation that shows a qualitatively similar …
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Metallorganische Chemische Gasphasenabscheidung (MOCVD) ferroelektrischer Dünnschichten : Herstellung und Charakterisierung
… films it could be shown by the method of reciprocal space mapping that the tilting angle of a-domains in c-axis oriented films is also being decreased by increasing barium content. This tilting effect is partially compensated by substrate induced compressive stress, which is comparable in …
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