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AuthorWang, Fengdc.contributor.author
Date of accession2017-04-27T07:49:09Zdc.date.accessioned
Available in OPARU since2017-04-27T07:49:09Zdc.date.available
Year of creation2016dc.date.created
Date of first publication2017-04-27dc.date.issued
AbstractA method for ab-initio structure factor retrieval from large-angle rocking-beam electron diffraction (LARBED)data of thin crystals is described and tested. This method determines crystal structure factors and specimen thickness from the intensities of the diffraction spots alone, solving a nonlinear least-squares problem. No additional information, such as atomicity or information about chemical composition, have been made use of. In addition to a demonstration of the method on 120 keV experimental data of SrTiO3, where 456 structure factors have been retrieved, we analyze the dependence of the success of the reconstruction on specimen thickness and tilt range by applying this algorithm to simulated data. Our numerical experiments show that the dynamical inversion by gradient optimization works best if the beam tilt range is large and the specimen not too thick. At specimen thicknesses which allow for moderate multiple scattering, the large tilt amplitude effectively removes local minima in this global optimization problem, making ab-initio structure factor retrieval possible. In addition, a dynamic parallelism framework based on the Compute Unified Device Architecture (CUDA) is introduced, reducing the runtime of the optimization routine by two orders of magnitude when compared to running on a CPU.dc.description.abstract
Languageen_USdc.language.iso
PublisherUniversität Ulmdc.publisher
LicenseStandarddc.rights
Link to license texthttps://oparu.uni-ulm.de/xmlui/license_v3dc.rights.uri
KeywordTransmission electron microscopydc.subject
KeywordInversion of dynamical scatteringdc.subject
KeywordAb-initio structure solutiondc.subject
KeywordStructure factor refinementdc.subject
Dewey Decimal GroupDDC 530 / Physicsdc.subject.ddc
LCSHElectrons; Diffractiondc.subject.lcsh
LCSHTransmission electron microscopydc.subject.lcsh
LCSHScattering (Physics)dc.subject.lcsh
TitleInversion of dynamical scattering from large-angle rocking-beam electron diffraction patternsdc.title
Resource typeDissertationdc.type
Date of acceptance2017-02-23dcterms.dateAccepted
RefereeKoch, Christophdc.contributor.referee
RefereeKaiser, Utedc.contributor.referee
DOIhttp://dx.doi.org/10.18725/OPARU-4325dc.identifier.doi
PPN887723446dc.identifier.ppn
URNhttp://nbn-resolving.de/urn:nbn:de:bsz:289-oparu-4364-5dc.identifier.urn
GNDDiffraktionsstreuungdc.subject.gnd
GNDDurchstrahlungselektronenmikroskopiedc.subject.gnd
FacultyFakultät für Naturwissenschaftenuulm.affiliationGeneral
InstitutionZE Elektronenmikroskopieuulm.affiliationSpecific
Shelfmark print versionW: W-H 15.094uulm.shelfmark
Grantor of degreeFakultät für Naturwissenschaftenuulm.thesisGrantor
DCMI TypeTextuulm.typeDCMI
TypeErstveröffentlichunguulm.veroeffentlichung
CategoryPublikationenuulm.category
In cooperation withHumboldt-Universität zu Berlinuulm.cooperation
University Bibliographyjauulm.unibibliographie


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