Giewekemeyer, Klaus

[["dc.bibliographiccitation.issue","1-2"],["dc.bibliographiccitation.volume","303"],["dc.contributor.author","Koelsch, P."],["dc.contributor.author","Viswanath, R."],["dc.contributor.author","Motschmann, H."],["dc.contributor.author","Shapovalov, V. L."],["dc.contributor.author","Brezesinski, G."],["dc.contributor.author","Moehwald, H."],["dc.contributor.author","Horinek, D."],["dc.contributor.author","Netz, R. R."],["dc.contributor.author","Giewekemeyer, K."],["dc.contributor.author","Salditt, T."],["dc.contributor.author","Schollmeyer, H."],["dc.contributor.author","Von Klitzing, R."],["dc.contributor.author","Daillant, J."],["dc.contributor.author","Guenoun, P."],["dc.date.accessioned","2017-09-07T11:49:26Z"],["dc.date.available","2017-09-07T11:49:26Z"],["dc.date.issued","2007"],["dc.description.abstract","Charged surfaces and ion-water interactions at an interface play a decisive role in many physico-chemical and biological processes. The classical treatment of ions at charged interfaces is the Poisson-Boltzmann (PB) theory. Despite severe simplifying assumptions it describes surprisingly well univalent ions not too close to the interface for low electrolyte concentrations in the mmol regime. However, it breaks down in the vicinity of the interface at higher surface charge densities. Consequently the list of decorations and modifications of the original PB equation is long aiming for a more realistic picture. One striking deficiency of the treatment on the pure electrostatic level is the prediction that ions of the same valence produce the same results, independent of their chemical nature. In contrast, experiments reveal pronounced differences between different ions. Specific ion effects can be found everywhere in chemistry and biology and there are many reports of pronounced differences in the properties of charged monolayers, micelles, vesicles, dispersions or polyelectrolyte multilayers using different identically charged counterions. The so-called \"counterion effect\" is usually discussed in terms of the Hofmeister series for cations or anions which are the result of a subtle balance of several competing evenly matched interactions. The complex interplay of electrostatics, dispersion forces, thermal motion, polarization, fluctuations, hydration, ion size effects and the impact of interfacial water structure makes it hard to identify a universal law. The diversity of specific ion effects is a direct consequence of this subtle interplay of forces and imposes a true challenge for the theories. The decisive information for an assessment of the theories is knowledge of the prevailing ion distribution. Hence a considerable amount of work has been applied to develop suitable model systems and to push surface characterization tools such as (resonant) X-ray reflectivity, total reflection X-ray fluorescence or X-ray standing waves to new limits. These techniques give direct information on the ions and on the interfacial architecture. A second alternative to complement these studies is infrared-visible sum frequency spectroscopy allowing to record surface vibrational spectra of the water as it is perturbed in the presence of the salts. The paper is organized in sections describing various facets of ion specific effects discussed within the network. (c) 2007 Elsevier B.V. All fights reserved."],["dc.identifier.doi","10.1016/j.colsurfa.2007.03.040"],["dc.identifier.gro","3143458"],["dc.identifier.isi","000247771200012"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/974"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Elsevier Science Bv"],["dc.publisher.place","Amsterdam"],["dc.relation.conference","French/ German Network on Complex Fluids - From 2D to 3D"],["dc.relation.eissn","1873-4359"],["dc.relation.eventlocation","Paris, FRANCE"],["dc.relation.ispartof","Colloids and Surfaces A: Physicochemical and Engineering Aspects"],["dc.relation.issn","0927-7757"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","molecular biophysics"],["dc.title","Specific ion effects in physicochemical and biological systems: Simulations, theory and experiments"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","227"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.lastpage","236"],["dc.bibliographiccitation.volume","19"],["dc.contributor.author","Krueger, S. P."],["dc.contributor.author","Neubauer, Heike"],["dc.contributor.author","Bartels, Matthias"],["dc.contributor.author","Kalbfleisch, Sebastian"],["dc.contributor.author","Giewekemeyer, Klaus"],["dc.contributor.author","Wilbrandt, P. J."],["dc.contributor.author","Sprung, Michael"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2017-09-07T11:48:58Z"],["dc.date.available","2017-09-07T11:48:58Z"],["dc.date.issued","2012"],["dc.description.abstract","The propagation of hard X-ray synchrotron beams in waveguides with guiding layer diameters in the 9-35 nm thickness range has been studied. The planar waveguide structures consist of an optimized two-component cladding. The presented fabrication method is suitable for short and leak-proof waveguide slices with lengths (along the optical axis) in the sub-500 mu m range, adapted for optimized transmission at photon energies of 11.5-18 keV. A detailed comparison between finite-difference simulations of waveguide optics and the experimental results is presented, concerning transmission, divergence of the waveguide exit beam, as well as the angular acceptance. In a second step, two crossed waveguides have been used to create a quasi-point source for propagation-based X-ray imaging at the new nano-focus endstation of the P10 coherence beamline at Petra III. By inverting the measured Fraunhofer diffraction pattern by an iterative error-reduction algorithm, a two-dimensional focus of 10 nm x 10 nm is obtained. Finally, holographic imaging of a lithographic test structure based on this optical system is demonstrated."],["dc.identifier.doi","10.1107/S0909049511051983"],["dc.identifier.gro","3142574"],["dc.identifier.isi","000300571300012"],["dc.identifier.pmid","22338684"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/8940"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","0909-0495"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY-NC 2.0"],["dc.subject.gro","x-ray optics"],["dc.title","Sub-10 nm beam confinement by X-ray waveguides: design, fabrication and characterization of optical properties"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.contributor.author","Kalbfleisch, Sebastian"],["dc.contributor.author","Neubauer, Heike"],["dc.contributor.author","Krüger, Sven P"],["dc.contributor.author","Bartels, Matthias"],["dc.contributor.author","Osterhoff, Markus"],["dc.contributor.author","Mai, Dong-Du"],["dc.contributor.author","Giewekemeyer, Klaus"],["dc.contributor.author","Hartmann, Britta"],["dc.contributor.author","Sprung, Michael"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.author","McNulty, Ian"],["dc.contributor.author","Eyberger, Catherine"],["dc.contributor.author","Lai, Barry"],["dc.date.accessioned","2017-09-07T11:54:07Z"],["dc.date.available","2017-09-07T11:54:07Z"],["dc.date.issued","2011"],["dc.identifier.doi","10.1063/1.3625313"],["dc.identifier.gro","3145117"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/2818"],["dc.language.iso","en"],["dc.notes.intern","Crossref Import"],["dc.notes.status","public"],["dc.publisher","AIP Publishing"],["dc.publisher.place","Melville, NY"],["dc.relation","SFB 755: Nanoscale Photonic Imaging"],["dc.relation.conference","10th International Conference on X-Ray Microscopy"],["dc.relation.eventend","2010-08-20"],["dc.relation.eventlocation","Chicago, Illinois"],["dc.relation.eventstart","2010-08-15"],["dc.relation.isbn","0-7354-0925-0"],["dc.relation.isbn","978-0-7354-0925-5"],["dc.relation.ispartof","The 10th International Conference on X-Ray Microscopy"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray optics"],["dc.subject.gro","x-ray imaging"],["dc.title","The Göttingen Holography Endstation of Beamline P10 at PETRA III∕DESY"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1986"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.lastpage","1995"],["dc.bibliographiccitation.volume","109"],["dc.contributor.author","Giewekemeyer, Klaus"],["dc.contributor.author","Hackenberg, C."],["dc.contributor.author","Aquila, Andrew"],["dc.contributor.author","Wilke, Robin Niklas"],["dc.contributor.author","Groves, M. R."],["dc.contributor.author","Jordanova, R."],["dc.contributor.author","Lamzin, V. S."],["dc.contributor.author","Borchers, G."],["dc.contributor.author","Saksl, K."],["dc.contributor.author","Zozulya, Alla L."],["dc.contributor.author","Sprung, M."],["dc.contributor.author","Mancuso, A. P."],["dc.date.accessioned","2018-11-07T09:49:05Z"],["dc.date.available","2018-11-07T09:49:05Z"],["dc.date.issued","2015"],["dc.description.abstract","The structural investigation of noncrystalline, soft biological matter using x-rays is of rapidly increasing interest. Large-scale x-ray sources, such as synchrotrons and x-ray free electron lasers, are becoming ever brighter and make the study of such weakly scattering materials more feasible. Variants of coherent diffractive imaging (CDI) are particularly attractive, as the absence of an objective lens between sample and detector ensures that no x-ray photons scattered by a sample are lost in a limited-efficiency imaging system. Furthermore, the reconstructed complex image contains quantitative density information, most directly accessible through its phase, which is proportional to the projected electron density of the sample. If applied in three dimensions, CDI can thus recover the sample's electron density distribution. As the extension to three dimensions is accompanied by a considerable dose applied to the sample, cryogenic cooling is necessary to optimize the structural preservation of a unique sample in the beam. This, however, imposes considerable technical challenges on the experimental realization. Here, we show a route toward the solution of these challenges using ptychographic CDI (PCDI), a scanning variant of coherent imaging. We present an experimental demonstration of the combination of three-dimensional structure determination through PCDI with a cryogenically cooled biological sample-a budding yeast cell (Saccharomyces cerevisiae)-using hard (7.9 keV) synchrotron x-rays. This proof-of-principle demonstration in particular illustrates the potential of PCDI for highly sensitive, quantitative three-dimensional density determination of cryogenically cooled, hydrated, and unstained biological matter and paves the way to future studies of unique, nonreproducible biological cells at higher resolution."],["dc.identifier.doi","10.1016/j.bpj.2015.08.047"],["dc.identifier.isi","000364009200024"],["dc.identifier.pmid","26536275"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/12679"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/35439"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation","SFB 755: Nanoscale Photonic Imaging"],["dc.relation.issn","1542-0086"],["dc.relation.issn","0006-3495"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY-NC-ND 4.0"],["dc.rights.uri","http://creativecommons.org/licenses/by-nc-nd/4.0/"],["dc.subject.gro","x-ray optics and imaging"],["dc.title","Tomography of a Cryo-immobilized Yeast Cell Using Ptychographic Coherent X-Ray Diffractive Imaging"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","18003"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Europhysics Letters (EPL)"],["dc.bibliographiccitation.volume","79"],["dc.contributor.author","Giewekemeyer, Klaus"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2017-09-07T11:49:27Z"],["dc.date.available","2017-09-07T11:49:27Z"],["dc.date.issued","2007"],["dc.description.abstract","We study the bromide counterion distribution near a solid-supported monolayer in the case of vanishing bulk electrolyte concentration by resonant X-ray reflectivity. The surface charge density of the monolayer was varied by using different molar ratios of the cationic Di-Octadecyl-Di-methyl-Ammonium-Bromide (DODAB) and the neutral Di-Palmitoyl-Glycero-Phosphocholine (DPPC). The analysis, either based on a conventional box model with an additional counterion contribution, or based on an independent unbiased global optimization approach, yields a good agreement with the classical Poisson- Boltzmann theory for the salt-free case. Copyright (c) EPLA, 2007."],["dc.identifier.doi","10.1209/0295-5075/79/18003"],["dc.identifier.gro","3143475"],["dc.identifier.isi","000248798000022"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/993"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","0295-5075"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","membrane biophysics"],["dc.title","Counterion distribution near a monolayer of variable charge density"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","035008"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","New Journal of Physics"],["dc.bibliographiccitation.volume","12"],["dc.contributor.affiliation","Giewekemeyer, K;"],["dc.contributor.affiliation","Neubauer, H;"],["dc.contributor.affiliation","Kalbfleisch, S;"],["dc.contributor.affiliation","Krüger, S P;"],["dc.contributor.author","Giewekemeyer, Klaus"],["dc.contributor.author","Neubauer, Heike"],["dc.contributor.author","Kalbfleisch, Sebastian"],["dc.contributor.author","Krueger, S. P."],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2017-09-07T11:46:08Z"],["dc.date.available","2017-09-07T11:46:08Z"],["dc.date.issued","2010"],["dc.date.updated","2022-02-09T21:48:01Z"],["dc.description.abstract","We report on lensless nanoscale imaging using x-ray waveguides as ultra-small sources for quasi-point-like illumination. We first give a brief account of the basic optical setup, an overview of the progress in waveguide fabrication and characterization, as well as the basics of image formation. We then compare one-step holographic and iterative ptychographic reconstruction, both for simulated and experimental data collected on samples illuminated by waveguided beams. We demonstrate that scanning the sample with partial overlap can substantially improve reconstruction quality in holographic imaging, and that divergent beams make efficient use of the limited dynamic range of current detectors, regardless of the reconstruction scheme. Among different experimental settings presented, smallest source dimensions of 29 nm (horizontal) x 17 nm have been achieved, using multi-modal interference effects. These values have been determined by ptychographic reconstruction of a Ta test structure at 17.5 keV and have been corroborated by simulations of field propagation inside the waveguide."],["dc.identifier.doi","10.1088/1367-2630/12/3/035008"],["dc.identifier.eissn","1367-2630"],["dc.identifier.fs","568205"],["dc.identifier.gro","3142948"],["dc.identifier.isi","000276349600007"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/6673"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/408"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","1367-2630"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","Goescholar"],["dc.rights.uri","https://goedoc.uni-goettingen.de/licenses"],["dc.subject.gro","x-ray optics"],["dc.subject.gro","x-ray imaging"],["dc.title","Holographic and diffractive x-ray imaging using waveguides as quasi-point sources"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.contributor.author","Kalbfleisch, Sebastian"],["dc.contributor.author","Osterhoff, Markus"],["dc.contributor.author","Giewekemeyer, Klaus"],["dc.contributor.author","Neubauer, Heike"],["dc.contributor.author","Krüger, Sven P"],["dc.contributor.author","Hartmann, Britta"],["dc.contributor.author","Bartels, Matthias"],["dc.contributor.author","Sprung, Michael"],["dc.contributor.author","Leupold, O."],["dc.contributor.author","Siewert, F."],["dc.contributor.author","Salditt, Tim"],["dc.contributor.author","Garrett, R."],["dc.contributor.author","Gentle, I."],["dc.contributor.author","Nugent, K."],["dc.contributor.author","Wilkins, S."],["dc.date.accessioned","2017-09-07T11:54:07Z"],["dc.date.available","2017-09-07T11:54:07Z"],["dc.date.issued","2010"],["dc.identifier.doi","10.1063/1.3463233"],["dc.identifier.gro","3145119"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/2820"],["dc.language.iso","en"],["dc.notes.intern","Crossref Import"],["dc.notes.status","public"],["dc.publisher","AIP Publishing"],["dc.publisher.place","Melville, NY"],["dc.relation","SFB 755: Nanoscale Photonic Imaging"],["dc.relation.conference","10th International Conference on Synchrotron Radiation Instrumentation"],["dc.relation.eventend","2009-10-02"],["dc.relation.eventlocation","Melbourne, Australia"],["dc.relation.eventstart","2009-09-27"],["dc.relation.isbn","978-0-7354-0782-4"],["dc.relation.ispartof","SRI 2009: the 10th International Conference on Synchrotron Radiation Instrumentation"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray optics"],["dc.subject.gro","x-ray imaging"],["dc.title","The holography endstation of beamline P10 at PETRA III"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","295"],["dc.bibliographiccitation.lastpage","296"],["dc.bibliographiccitation.volume","2007"],["dc.contributor.author","Beerlink, André"],["dc.contributor.author","Boye, P."],["dc.contributor.author","Giewekemeyer, Klaus"],["dc.contributor.author","Gulden, Johannes"],["dc.contributor.author","Meents, Alke"],["dc.contributor.author","Neubauer, H."],["dc.contributor.author","Schropp, Andreas"],["dc.contributor.author","Stephan, S."],["dc.contributor.author","Salditt, Tim"],["dc.contributor.author","Schroer, Christian G."],["dc.contributor.author","Vartaniants, I."],["dc.contributor.author","Weckert, E."],["dc.date.accessioned","2020-03-11T10:13:50Z"],["dc.date.available","2020-03-11T10:13:50Z"],["dc.date.issued","2007"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/63298"],["dc.language.iso","en"],["dc.notes.preprint","yes"],["dc.relation.crisseries","Jahresbericht (Hamburger Synchrotronstrahlungslabor am Deutschen Elektronen-Synchrotron DESY)"],["dc.relation.eventend","2007"],["dc.relation.eventlocation","Hamburg"],["dc.relation.eventstart","2007"],["dc.relation.iserratumof","yes"],["dc.relation.ispartofseries","HASYLAB Jahresbericht;"],["dc.title","Coherent X-ray Diffraction Measurements at the cSAX beamline at SLS"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","012175"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","AIP Advances"],["dc.bibliographiccitation.volume","2"],["dc.contributor.author","Ruhlandt, A."],["dc.contributor.author","Liese, T."],["dc.contributor.author","Radisch, V."],["dc.contributor.author","Krüger, S. P."],["dc.contributor.author","Osterhoff, M."],["dc.contributor.author","Giewekemeyer, K."],["dc.contributor.author","Krebs, H.-U."],["dc.contributor.author","Salditt, T."],["dc.date.accessioned","2017-09-07T11:48:57Z"],["dc.date.available","2017-09-07T11:48:57Z"],["dc.date.issued","2012"],["dc.description.abstract","We have used a combined optical system of a high gain elliptic Kirkpatrick-Baez mirror system (KB) and a multilayer Laue lens (MLL) positioned in the focal plane of the KB for hard x-rays nano-focusing. The two-step focusing scheme is based on a high acceptance and high gain elliptical mirror with moderate focal length and a MLL with ultra-short focal length. Importantly, fabrication constraints, i.e. in mirror polishing and bending, as well as MLL deposition can be significantly relaxed, since (a) the mirror focus in the range of 200-500 nm is sufficient, and (b) the number of layers of the MLL can be correspondingly small. First demonstrations of this setup at the coherence beamline of the PETRA III storage ring yield a highly divergent far-field diffraction pattern, from which the autocorrelation function of the near-field intensity distribution was obtained. The results show that the approach is well suited to reach smallest spot sizes in the sub-10nm range at high flux. Copyright 2012 Author(s). This article is distributed under a Creative Commons Attribution 3.0 Unported License. [http://dx.doi.org/10.1063/1.3698119]"],["dc.identifier.doi","10.1063/1.3698119"],["dc.identifier.fs","589570"],["dc.identifier.gro","3142567"],["dc.identifier.isi","000302225400093"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/9557"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/8932"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation","SFB 755: Nanoscale Photonic Imaging"],["dc.relation.issn","2158-3226"],["dc.relation.orgunit","Fakultät für Physik"],["dc.relation.orgunit","Institut für Materialphysik"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray optics"],["dc.title","A combined Kirkpatrick-Baez mirror and multilayer lens for sub-10 nm x-ray focusing"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","051604"],["dc.bibliographiccitation.issue","5"],["dc.bibliographiccitation.journal","Physical Review E"],["dc.bibliographiccitation.volume","77"],["dc.contributor.author","Hohage, Thorsten"],["dc.contributor.author","Giewekemeyer, Klaus"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2017-09-07T11:48:45Z"],["dc.date.available","2017-09-07T11:48:45Z"],["dc.date.issued","2008"],["dc.description.abstract","Analysis of x-ray and neutron reflectivity is usually performed by modeling the density profile of the sample and performing a least square fit to the measured (phaseless) reflectivity data. Here we address the uniqueness of the reflectivity problem as well as its numerical reconstruction. In particular, we derive conditions for uniqueness, which are applicable in the kinematic limit (Born approximation), and for the most relevant case of box model profiles with Gaussian roughness. At the same time we present an iterative method to reconstruct the profile based on regularization methods. The method is successfully implemented and tested both on simulated and real experimental data."],["dc.identifier.doi","10.1103/PhysRevE.77.051604"],["dc.identifier.gro","3143313"],["dc.identifier.isi","000256885400068"],["dc.identifier.pmid","18643076"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/814"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","1539-3755"],["dc.relation.orgunit","Institut für Numerische und Angewandte Mathematik"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray scattering"],["dc.title","Iterative reconstruction of a refractive-index profile from x-ray or neutron reflectivity measurements"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]