31708
2009
2009
eng
article
1
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Bimodal temperature behavior of structure and mobility in high molecular weight p3ht thin films
We report a temperature dependent crystalline structure of spin-coated thin films of high molecular weight regioregular poly(3-hexylthiophene) (P3HT) (M-n similar to 30000 g/mol) and its correlation with charge carrier mobility. These investigations show a reversible change of the crystalline structure, where the interlayer lattice spacing (100)along the alkyl side chains continuously increases up to a temperature of about 220 degrees C; in contrast, the in-plane pi-pi distance reduces with increasing temperature. These changes in structure are reversible and can be repeated several times. The temperature-induced structural properties differ for thick and thin films, pointing to a surface/interface role in stabilization of the layer morphology. In contrast to the structural changes, the carrier mobility is rather constant in the temperature range from room temperature up to 100-120 degrees C, followed by a continuous decrease. For thick layers this drop is significant and the transistor performance almost vanishes at high temperature, however, it completely recovers upon cooling back to roorn temperature. The drop of the charge carrier mobility at higher temperatures is in contrast with expectations front the structural studies, considering the increase of crystalline fraction of the polycrystalline layer. our electrical measurements Underscore that the reduction of the macroscopic mobility is mostly caused by it pronounced decrease of the intergrain transport. The thermally induced crystallization along(100) direction and the creation of numerous small crystallites at the film-substrate interface reduce the number of long polymer chain, bridging crystalline domains, which ultimately limits the macroscopic charge transport.
http://pubs.acs.org/journal/mamobx
10.1021/Ma900021w
0024-9297
allegro:1991-2014
10108046
Macromolecules. - ISSN 0024-9297. - 42 (2009), 13, S. 4651 - 4660
Siddharth Joshi
Patrick Pingel
Souren Grigorian
Tobias Panzner
Ullrich Pietsch
Dieter Neher
Michael Forster
Ullrich Scherf
Institut für Physik und Astronomie
Referiert
32457
2006
2006
eng
article
1
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Effect of molecular weight on the structure and crystallinity of poly(3-hexylthiophene)
Recently, two different groups have reported independently that the mobility of field-effect transistors made from regioregular poly(3-hexylthiophene) (P3HT) increases strongly with molecular weight. Two different models were presented: one proposing carrier trapping at grain boundaries and the second putting emphasis on the conformation and packing of the polymer chains in the thin layers for different molecular weights. Here, we present the results of detailed investigations of powders and thin films of deuterated P3HT fractions with different molecular weight. For powder samples, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) were used to investigate the structure and crystallization behavior of the polymers. The GPC investigations show that all weight fractions possess a rather broad molecular weight distribution. DSC measurements reveal a strong decrease of the crystallization temperature and, most important, a significant decrease of the degree of crystallinity with decreasing molecular weight. To study the structure of thin layers in lateral and vertical directions, both transmission electron microscopy (TEM) and X-ray grazing incidence diffraction (GID) were utilized. These methods show that thin layers of the low molecular weight fraction consist of well-defined crystalline domains embedded in a disordered matrix. We propose that the transport properties of layers prepared from fractions of poly(3-hexylthiophene) with different molecular weight are largely determined by the crystallinity of the samples and not by the perfection of the packing of the chains in the individual crystallites
http://pubs.acs.org/doi/full/10.1021/ma0521349
10.1021/Ma0521349
allegro:1991-2014
10101591
Macromolecules. - 39 (2006), 6, S. 2162 - 2171
Achmad Zen
Marina Saphiannikova
Dieter Neher
Jörg Grenzer
Souren A. Grigorian
Ullrich Pietsch
Udom Asawapirom
Silvia Janietz
Ullrich Scherf
Ingo Lieberwirth
Gerhard Wegner
Institut für Chemie
Referiert
13507
2005
2005
eng
article
1
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Structure and temperature behavior of metallo-supramolecular assemblies
A detailed structural analysis of a Langmuir-Blodgett (LB) multilayer composed of a polyelectrolyte-amphiphile complex (PAC) is presented. The PAC is self-assembled from metal ions, ditopic bis-terpyridines, and amphiphiles. The vertical structure of the LB multilayer is investigated by X-ray reflectometry. The multilayer has a periodicity of 57 A, which corresponds to an architecture of flat lying metallo-supramolecular coordination polyelectrolyte (MEPE) rods and upright-standing amphiphiles (dihexadecyl phosphate, DHP). In-plane diffraction reveals hexagonal packing of the DHP molecules. Using extended X-ray absorption fine structure (EXAFS) experiments, we prove that the central metal ion is coordinated to the terpyridine moieties in a pseudo-octahedral coordination environment. The Fe-N bond distances are 1.82 and 2.0 angstrom, respectively. Temperature resolved measurements indicate a reversible phase transition in a temperature range up to 55 degrees C. EXAFS measurements indicate a lengthening of the average Fe-N bond distance from 1.91 to 1.95 angstrom. The widening of the coordination cage upon heating is expected to lower the ligand field stabilization, thus giving rise to spin transitions in these composite materials
allegro:1991-2014
10098937
Journal of physical chemistry / B. - 109 (2005), 26, S. 12795 - 12799
Ullrich Pietsch
Yves Bodenthin
Jörg Grenzer
Thomas Geue
Helmuth Möhwald
Dirk G. Kurth
Institut für Physik und Astronomie
Referiert
Institut für Physik
13498
2005
2005
eng
article
1
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Glass transition in Ultrathin Polymer Films : a Thermal Expansion Study
The glass transition process gets affected in ultrathin films having thickness comparable to the size of the molecules. We observe systematic broadening of the glass transition temperature (T-g) as the thickness of an ultrathin polymer film reduces below the radius of gyration but the change in the average T-g was found to be very small. The existence of reversible negative and positive thermal expansion below and above T-g increased the sensitivity of our thickness measurements performed using energy-dispersive x-ray reflectivity. A simple model of the T-g variation as a function of depth expected from sliding motion could explain the results
allegro:1991-2014
10098936
Physical Review / E. - 71 (2005), 4, S. 5
Ullrich Pietsch
M. K. Bhattacharya
M. K. Sanyal
Thomas Geue
Institut für Physik und Astronomie
Referiert
Institut für Physik
13516
2005
2005
eng
article
1
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Grazing-incidence diffraction strain analysis of a laterally patterned Si wafer treated by focused Ge and An ion beam implantation
Strain analysis of a laterally patterned Si-wafer was carried out utilizing X-ray grazing-incidence diffraction with synchrotron radiation. The lateral patterning was done by focused ion beam implantation using an ion source of liquid AuGeSi alloy. Samples were prepared by either 35 keV Au+ ions (dose: 0.2, 2 x 10(14) cm(-2)) or 70 keV Ge++ ions (dose: 8 X 10(14) cm(-1)). It was shown that due to implantation a periodical defect structure is created consisting of both implanted and not implanted stripes. The evaluated depth distribution of defects within the implanted stripes corresponds to that obtained by TRIM calculation. The induced strain distribution, however, shows no periodicity. This can be explained by an overlap of the strain fields created in each implanted stripe. (c) 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
allegro:1991-2014
10098935
Physica status solidi / A. - 202 (2005), 6, S. 1009 - 1016
Ullrich Pietsch
Jörg Grenzer
Lothar Bischoff
Institut für Physik und Astronomie
Referiert
Open Access
Institut für Physik
13486
2005
2005
eng
article
1
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Inducing spin crossover in metallo-supramolecular polyelectrolytes through an amphiphilic phase transition
A phase transition in an amphiphilic mesophase is explored to deliberately induce mechanical strain in an assembly of tightly coupled metal ion coordination centers. Melting of the alkyl chains in the amphiphilic mesophase causes distortion of the coordination geometry around the central transition metal ion. As a result, the crystal field splitting of the d-orbital subsets decreases resulting in a spin transition from a low-spin to a high-spin state. The diamagnetic-paramagnetic transition is reversible. This concept is demonstrated in a metallo-supramolecular coordination polyelectrolyte-amphiphile complex self-assembled from ditopic bis-terpyridines, Fe(II) as central transition metal, and dialkyl phosphates as amphiphiles. The magnetic properties are studied in a Langmuir-Blodgett multilayer. The modularity of this concept provides extensive control of structure and function from molecular to macroscopic length scales and gives access to a wide range of new molecular magnetic architectures such as nanostructures, thin films, and liquid crystals
allegro:1991-2014
10098930
Journal of the American Chemical Society. - 127 (2005), 9, S. 3110 - 3114
Ullrich Pietsch
Yves Bodenthin
Helmuth Möhwald
Dirk G. Kurth
Institut für Physik und Astronomie
Referiert
Institut für Physik
13655
2005
2005
eng
article
1
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X-ray diffraction by a crystal in a permanent external electric field : general considerations
The variations of X-ray diffraction intensities from a crystal in the presence of a permanent external electric field is modeled analytically using a first-order stationary perturbation theory. The change in a crystal, induced by an external electric field, is separated into two contributions. The first one is related to a pure polarization of an electron subsystem, while the second contribution can be reduced to the displacements of the rigid pseudoatoms from their equilibrium positions. It is shown that a change of the X-ray diffraction intensities mainly originates from the second contribution, while the influence of the pure polarization of a crystal electron subsystem is negligibly small. The quantities restored from an X-ray diffraction experiment in the presence of an external electric field were analyzed in detail in terms of a rigid pseudoatomic model of electron density and harmonic approximation for the atomic thermal motion. Explicit relationships are derived that link the properties of phonon spectra with E-field-induced variations of a structure factor, pseudoatomic displacements and piezoelectric strains. The displacements can be numerically estimated using a model of independent atomic motion if the Debye - Waller factors and pseudoatomic charges are known either from a previous single-crystal X-ray diffraction study or from density functional theory calculations. The above estimations can be used to develop an optimum strategy for a data collection that avoids the measurements of reflections insensitive to the electric-field-induced variations
0108-7673
allegro:1991-2014
10103799
Acta Crystallographica / A. - ISSN 0108-7673. - 61 (2005), S. 387 - 396
S. V. Gorfman
Vladimir G. Tsirelson
Ullrich Pietsch
Institut für Physik und Astronomie
Referiert
Institut für Physik
13696
2005
2005
eng
article
1
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From anisotropic photo-fluidity towards nanomanipulation in the optical near-field
An increase in random molecular vibrations of a solid owing to heating above the melting point leads to a decrease in its long-range order and a loss of structural symmetry. Therefore conventional liquids are isotropic media. Here we report on a light-induced isothermal transition of a polymer film from an isotropic solid to an anisotropic liquid state in which the degree of mechanical anisotropy can be controlled by light. Whereas during irradiation by circular polarized light the film behaves as an isotropic viscoelastic fluid, it shows considerable fluidity only in the direction parallel to the light field vector under linear polarized light. The fluidization phenomenon is related to photoinduced motion of azobenzene-functionalized molecular units, which can be effectively activated only when their transition dipole moments are oriented close to the direction of the light polarization. We also describe here how the photofluidization allows nanoscopic elements of matter to be precisely manipulated
1476-1122
allegro:1991-2014
10103851
Nature Materials. - ISSN 1476-1122. - 4 (2005), 9, S. 699 - 703
Peter Karageorgiev
Dieter Neher
Burkhard Schulz
Burkhard Stiller
Ullrich Pietsch
Michael Giersig
Ludwig Brehmer
Institut für Physik und Astronomie
Referiert
Institut für Physik
13826
2005
2005
eng
article
1
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Coherence experiments using white synchrotron radiation
Experiments at the bending magnet beamline at BESSY II (EDR beamline) profit from the excellent coherence properties of third generation synchrotron sources. Considering the exponentially decaying incident spectrum, and because no optical elements are installed except slits and vacuum windows, coherence experiments can be performed between 5 keV < E < 15 keV. First, the energy dependence of spatial coherence properties were determined measuring diffraction at single and double pinholes. Next, the coherent white radiation was used to probe the morphology of thin films in reflection geometry. The recorded intensity maps (reflectivity versus sample position) provide speckle patterns which reveal the locally varying sample morphology. Setting the incident angle, alpha(i), smaller or larger than the critical angle of total external reflection, alpha(c), one should be able to separate the surface height profile from the subsurface density modulation of a sample. The validity of this approach is verified at the example of reciprocal space maps taken from a polymer surface where we could reconstruct the lateral height profile from speckle data. (C) 2004 Elsevier B.V. All rights reserved
allegro:1991-2014
10104148
Physica / b. - 357 (2005), 1-2, S. 45 - 52
Ullrich Pietsch
Tobias Panzner
Wolfram Leitenberger
Ivan A. Vartanyants
Institut für Physik und Astronomie
Referiert
Institut für Physik
14384
2004
2004
eng
article
1
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In-situ Investigation of Surface Relief Grating Formation in Photosensitive Polymers
http://www.chess.cornell.edu/pubs/csnm2004/research/insitu.pdf
allegro:1991-2014
10097663
Chess News Magazine. - 2004, S. 39 - 41
Oliver Henneberg
Paul Rochon
Tobias Panzner
Kenneth D. Finkelstein
Thomas Geue
Marina Saphiannikova
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
Nicht ermittelbar
12175
2007
2007
eng
article
1
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A monolithic Fresnel bimirror for hard X-rays and its application for coherence measurements
Experiments using a simple X-ray interferometer to measure the degree of spatial coherence of hard X-rays are reported. A monolithic Fresnel bimirror is used at small incidence angles to investigate synchrotron radiation in the energy interval 5-50 keV with monochromatic and white beam. The experimental setup was equivalent to a Young's double-slit experiment for hard X-rays with slit dimensions in the micrometre range. From the high-contrast interference pattern the degree of coherence was determined.
http://journals.iucr.org/s/issues/2007/02/00/wl5137/wl5137.pdf
10.1107/S0909049507003846
0909-0495
allegro:1991-2014
10103390
Journal of synchrotron radiation. - ISSN 0909-0495. - 14 (2007), S. 196 - 203
Wolfram Leitenberger
Ullrich Pietsch
Institut für Physik und Astronomie
Referiert
Institut für Physik
12309
2006
2006
eng
article
1
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X-ray diffraction by a crystal in a permanent external electric field : electric-field-induced structural response in alpha-GaPO4
For the first time, site-selective distortion has been investigated for two different structural units in the ternary compound alpha-GaPO4 under the influence of a permanent external electric field. Based on 54 measured reflection intensities, the electric-field-induced distortion of PO4 and GaO4 tetrahedra in alpha-GaPO4 crystals is evaluated using a model of pseudoatomic displacements introduced recently [Gorfman, Tsirelson & Pietsch (2005). Acta Cryst. A61, 387- 396]. A stronger variation of the P-O bond lengths in the PO4 tetrahedron was found compared to the bonds in the GaO4 tetrahedron. The different distortions of the tetrahedra owing to the electric field were analysed in terms of the valence charge density of alpha-GaPO4 and its topological characteristics. The larger charge of the P pseudoatom compared to the Ga atom was recognized as the main reason for the higher sensitivity of the PO4 tetrahedron to a permanent external electric field
http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1600-5724
10.1107/S0108767305036111
0108-7673
allegro:1991-2014
10101606
Acta crystallographica / a. - ISSN 0108-7673. - 62 (2006)
Semen Gorfman
Vladimir Tsirelson
Andreas Pucher
Wolfgang Morgenroth
Ullrich Pietsch
Institut für Chemie
Referiert
12862
2005
2005
eng
article
1
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Coherence experiments at the EDR-beamline of BESSY II
allegro:1991-2014
10098933
Physica / B. - 357 (2005), 1-2, S. 45 - 52
Ullrich Pietsch
Tobias Panzner
Wolfram Leitenberger
Ivan A. Vartanyants
Institut für Physik und Astronomie
Referiert
Institut für Physik
13404
2005
2005
eng
article
1
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Carrier dynamics in laterally strain-modulated InGaAs quantum wells
We investigate the transient recombination and transfer properties of nonequilibrium carriers in an In0.16Ga0.84As/GaAs quantum well (QW) with an additional lateral confinement implemented by a patterned stressor layer. The structure thus contains QW- and quantum-wire-like areas. At low excitation densities, photoluminescence (PL) transients from both areas are well described by a rate equation model for a three-level system with a saturable interlevel carrier transfer representing the lateral drift of carriers from the QW regions into the wires. Small-signal carrier lifetimes for QW, wires, and transfer time from QW to wire are 180, 190, and 28 ps, respectively. For high excitation densities the time constants of the observed transients increase, in agreement with the model. In addition, QW and wire PL lines merge indicating a smoothening of the potential difference, i.e., the effective carrier confinement caused by the stressor structure becomes weaker with increasing excitation. (c) 2005 American Institute of Physics
allegro:1991-2014
10101615
Applied physics letters. - 87 (2005), 26
V Talalaev
JW Tomm
T Elsaesser
Ute Zeimer
J Fricke
A Knauer
H Kissel
Markus Weyers
GG Tarasov
Jörg Grenzer
Ullrich Pietsch
Institut für Physik und Astronomie
Referiert
Institut für Physik
13821
2005
2005
eng
article
1
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Substrate morphology repetition in "thick" polymer films
Using Grazing-incidence small-angle scattering (GISAXS) technique we investigated the surface morphology of polymer films spin-coated on different silicon substrates. As substrates we used either technologically smooth silicon wafers or the same silicon wafer coated with thin aluminium or gold films which show a granular structure at the surface. Although the polymer thickness exceeds 300 nm the GISAXS pattern of the film shows the same in-plane angle distribution Delta2theta as the underlying substrate. Annealing the polymer films at a temperature above its glass transition temperature Delta2theta changed from a broad to a narrow distribution as it is typically for films on pure silicon. The experiment can be interpreted by roughness replication and density fluctuation within the polymer film created while spin-coating at room temperature. Due to the low segment mobility there are density fluctuations which repeat the surface morphology of the substrate. Above the glass temperature the polymer density can be homogenized independently from the morphology of the substrate. (C) 2004 Elsevier B.V. All rights reserved
allegro:1991-2014
10098934
Physica / B. - 357 (2005), 1-2, S. 136 - 140
Ullrich Pietsch
Tobias Panzner
Franz Pfeiffer
Ian K. Robinson
Institut für Physik und Astronomie
Referiert
Institut für Physik
13923
2005
2005
eng
article
1
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Optimised two layer overgrowth of a lateral strain-modulated nanostructure
Recently it has been shown that lateral carrier confinement in an InGaAs quantum well (QW) embedded in GaAs can be achieved by using a laterally patterned InGaP stressor layer on top of the heterostructure. To exploit this effect in a device the structure has to be planarized by a second epitaxial step. It has been shown that the lateral strain modulation almost vanishes after overgrowth with GaAs, whereas overgrowth with a single ternary layer of opposite strain compared to the stressor layer suffers from strain induced decomposition. Here we show that the lateral carrier confinement of the initially free standing nanostructure can almost be maintained using a two step process for overgrowth, where a strained thin ternary layer is grown first followed by GaAs up to complete planarization of the patterned structure. Thickness and composition of the ternary layer are adjusted on the basis of finite element calculations of the strain distribution (FEM). The strain field achieved after overgrowth is probed by X-ray grazing- incidence diffraction (GID). (c) 2005 Elsevier B.V. All rights reserved
0925-8388
allegro:1991-2014
10104407
Journal of Alloys and Compounds. - ISSN 0925-8388. - 401 (2005), 1-2, S. 226 - 230
Ute Zeimer
Ullrich Pietsch
Joerg Grenzer
J. Fricke
A. Knauer
Markus Weyers
Institut für Physik und Astronomie
Referiert
Institut für Physik
14529
2004
2004
eng
XVI, 408 S. : graph. Darst.
2. ed.
book
Springer
New York
1
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High resolution X-ray scattering from thin films and lateral nanostructures
Advanced texts in physics : physics and astronomy online library
0-387-40092-3
allegro:1991-2014
10098938
Ullrich Pietsch
Václav Holý
Tilo Baumbach
Institut für Physik und Astronomie
Institut für Physik
14827
2004
2004
eng
article
1
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Non-linear effects during inscription of azobenzene surface relief gratings
allegro:1991-2014
10098918
Journal of physical chemistry / b. - 108 (2004), 39, S. 15084 - 15089
Ullrich Pietsch
Marina Saphiannikova
Oliver Henneberg
Thomas Geue
Institut für Physik und Astronomie
Referiert
Institut für Physik
15061
2004
2004
eng
article
1
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Nonlinear effects during inscription of azobenzene surface relief gratings
Surface relief gratings were inscribed on azobenzene polymer films using a pulselike exposure of an Ar+ laser. The inscription process was initiated by a sequence of short pulses followed by much longer relaxation pauses. The development of the surface relief grating was probed by a He-Ne laser measuring the scattering intensity of the first- order grating peak. The growth time of the surface relief grating was found to be larger than the length of the pulses used. This unusual behavior can be considered as a nonlinear material response associated with the trans-cis isomerization of azobenzene moieties. In this study the polymer stress was assumed to be proportional to the number of cis-isomers. One-dimensional viscoelastic analysis was used to derive the polymer deformation. The rate of trans-cis isomerization increases with the intensity of the inscribing light; in the dark it is equal to the rate of thermal cis- trans isomerization. The respective relaxation times were estimated by fitting theoretical deformation curves to experimental data
1520-6106
allegro:1991-2014
10102916
Journal of Physical Chemistry / B. - ISSN 1520-6106. - 108 (2004), 39, S. 15084 - 15089
Marina Saphiannikova
Oliver Henneberg
T. M. Gene
Ullrich Pietsch
Paul Rochon
Institut für Physik und Astronomie
Referiert
Institut für Physik
15036
2004
2004
eng
article
1
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Iron self-diffusion in nanocrystalline FeCr thin films
Thin films of amorphous Fe85Zr15 alloy were deposited by ion-beam sputtering of a composite target. Analogous to the melt-spun amorphous alloys of similar composition, the crystallization of the amorphous film occurs in two steps, however, with a substantially reduced thermal stability. After completion of the first crystallization step which starts at 473 K, the microstructure consists of 12 nm nanocrystals of bcc-Fe embedded in a grain boundary region of the remaining amorphous phase. At 673 K, the remaining amorphous phase transforms into the Fe2Zr alloy. The self-diffusion measurements of iron in the nanocrystalline state and in the parent amorphous state has been carried out using secondary ion mass spectroscopy (SIMS) depth profiling and neutron reflectivity techniques. In contrast to the case of finemet Fe73.5Si13.5B9Nb3Cu1 alloy, where a significant enhancement of diffusivity takes place in the nanocrystalline state, in the present case the diffusivity in the nanocrystalline state is similar to that in the parent amorphous state. It is suggested that in this system the atomic diffusion occurs mainly via the grain boundary regions. The calculated values of the pre-exponential factor and the activation energy for the diffusion are D-0 = 1 x 10(-14+/-1) m(2)/s and E = (0.7 +/- 0.1) eV respectively. (C) 2004 Published by Elsevier B.V.
allegro:1991-2014
10098889
Journal of non-crystalline solids. - 343 (2004), 1 - 3, S. 39 - 47
Ullrich Pietsch
Ajay Gupta
Mukul Gupta
S. Ayachit
S. Rajagopalan
A. K. Balamurgan
A. K. Tyagi
Institut für Physik und Astronomie
Referiert
Institut für Physik
15065
2004
2004
eng
article
1
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Nanoengineering of lateral strain-modulation in quantum well heterostructures
We have developed a method to design a lateral band-gap modulation in a quantum well heterostructure. The lateral strain variation is induced by patterning of a stressor layer grown on top of a single quantum well which itself is not patterned. The three-dimensional (3D) strain distribution within the lateral nanostructure is calculated using linear elasticity theory applying a finite element technique. Based on the deformation potential approach the calculated strain distribution is translated into a local variation of the band-gap energy. Using a given vertical layer structure we are able to optimize the geometrical parameters to provide a nanostructure with maximum lateral band-gap variation. Experimentally such a structure was realized by etching a surface grating into a tensile-strained InGaP stressor layer grown on top of a compressively strained InGaAs-single quantum well. The achieved 3D strain distribution and the induced band-gap variation are successfully probed by x-ray grazing incidence diffraction and low-temperature photoluminescence measurements, respectively
allegro:1991-2014
10098912
Physical review / b. - 69 (2004), 12, S. 8, Art. Nr. 125316
Ullrich Pietsch
Jörg Grenzer
Souren A. Grigorian
Markus Weyers
Ute Zeimer
S. Feranchuk
J. Fricke
H. Kissel
A. Knauer
G. Tränkle
Institut für Physik und Astronomie
Referiert
Institut für Physik
15139
2004
2004
eng
article
1
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Ripple structure of crystalline layers in ion beam induced Si wafers
Ion-beam-induced ripple formation in Si wafers was studied by two complementary surface sensitive techniques, namely atomic force microscopy (AFM) and depth-resolved x-ray grazing incidence diffraction (GID). The formation of ripple structure at high doses (similar to7x10(17) ions/cm(2)), starting from initiation at low doses (similar to1x10(17) ions/cm(2)) of ion beam, is evident from AFM, while that in the buried crystalline region below a partially crystalline top layer is evident from GID study. Such ripple structure of crystalline layers in a large area formed in the subsurface region of Si wafers is probed through a nondestructive technique. The GID technique reveals that these periodically modulated wavelike buried crystalline features become highly regular and strongly correlated as one increases the Ar ion-beam energy from 60 to 100 keV. The vertical density profile obtained from the analysis of a Vineyard profile shows that the density in the upper top part of ripples is decreased to about 15% of the crystalline density. The partially crystalline top layer at low dose transforms to a completely amorphous layer for high doses, and the top morphology was found to be conformal with the underlying crystalline ripple
allegro:1991-2014
10098917
Physical review / b. - 70 (2004), 12, Art. Nr. 121307 (R)
Ullrich Pietsch
S. Hazra
T. K. Chini
M. K. Sanyal
Jörg Grenzer
Institut für Physik und Astronomie
Referiert
Institut für Physik
15130
2004
2004
eng
article
1
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Structural characterization of epitaxial Fe/Cr multilayers using anomalous x-ray scattering and neutron reflectivity
The interface structure of epitaxial Fe/Cr multilayers was studied using anomalous X-ray and neutron reflectivity. The analysis of X-ray reflectivity at three different energies provided a reliable information about the interface roughnesses. It is found that the Cr-on-Fc interface is more diffused as compared to the Fe-on-Cr interface and that the roughness exhibits a significant increase with increasing depth. The magnetic roughness, as determined from neutron reflectivity, is lower than the geometrical roughness, in conformity with the behavior of a number of magnetic thin films and multilayers. (C) 2004 Elsevier B.V. All rights reserved
allegro:1991-2014
10098913
Journal of Magnetism and Magnetic Materials. - 272 (2004), 2, S. 1219 - 1220
Ullrich Pietsch
Amod Gupta
A. Paul
C. Meneghini
K. Mibu
S. Maddalena
S. Dal Toe
G. Principi
Institut für Physik und Astronomie
Referiert
Institut für Physik
15175
2004
2004
eng
article
1
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Investigation of azobenzene side group orientation in polymer surface relief gratings by means of photoelectron spectroscopy
The molecular orientation of azobenzene side groups in polymer films before (nonpatterned) and after (patterned) development of a surface relief grating has been investigated by photoelectron spectroscopy using synchrotron radiation. The photoemission spectra obtained for 60-100 eV photons of a patterned and a nonpatterned surface are similar when the polarization vector of the synchrotron light is parallel to the grating vector. However, for perpendicular excitation, considerable spectral intensity differences can be observed for 9-14 eV electron binding energy. The observed changes are attributed to the formation of well-oriented azobenzenes at the surface. (C) 2004 American Institute of Physics
http://scitation.aip.org/journals/doc/APPLAB-ft/vol_84/iss_9/1561_1.html
allegro:1991-2014
10097657
Applied physics letters. - 84 (2004), 9, S. 1561 - 1563
Oliver Henneberg
Thomas Geue
Ullrich Pietsch
Bernd Winter
Institut für Physik und Astronomie
Referiert
Institut für Physik
15193
2004
2004
eng
article
1
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White beam x-ray waveguide optics
We report a white beam x-ray waveguide (WG) experiment. A resonant beam coupler x-ray waveguide (RBC) is used simultaneously as a broad bandpass (or multibandpass) monochromator and as a beam compressor. We show that, depending on the geometrical properties of the WG, the exiting beam consists of a defined number of wavelengths which can be shifted by changing the angle of incidence of the white x-ray synchrotron beam. The characteristic far-field pattern is recorded as a function of exit angle and energy. This x-ray optical setup may be used to enhance the intensity of coherent x-ray WG beams since the full energetic acceptance of the WG mode is transmitted. (C) 2004 American Institute of Physics
allegro:1991-2014
10098916
Applied physics letters. - 85 (2004), 2, S. 161 - 163
Ullrich Pietsch
A. Jarre
T. Salditt
Tobias Panzner
F. Pfeiffer
Institut für Physik und Astronomie
Referiert
Institut für Physik
15353
2004
2004
eng
article
1
--
--
--
Transition from two-dimensional to three-dimensional melting in Langmuir-Blodgett films
Results of energy-dispersive x-ray reflectivity and grazing incidence diffraction studies of Langmuir-Blodgett films exhibited evolution of conventional three-dimensional melting from continuous melting, characteristic of two- dimensional systems, as a function of deposited monolayers. Continuous expansion followed by a sharp phase transition of the in-plane lattice was observed before the melting point and found to be independent of number of deposited layers. Evolution of conventional melting with an increase in the number of monolayers could be quantified by measuring stiffness against tilting of the vertical stack of molecules, which are kept together by an internal field. The internal field as defined in this model reduces as the in-plane lattice expands and the sample temperature approaches melting point. The sharpness of the melting transition, which has been approximated by a Langevin function, increases with the number of deposited monolayers
allegro:1991-2014
10098910
Physical Review / B. - 70 (2004), 24, S. 9, Art. Nr. 245408
Ullrich Pietsch
M. K. Mukhopadhyay
M. K. Sanyal
A. Datta
M. Mukherjee
Thomas Geue
Jörg Grenzer
Institut für Physik und Astronomie
Referiert
Institut für Physik
15342
2004
2004
eng
article
1
--
--
--
The atomistic origin of the inverse piezoelectric effect in a-quartz
Ab initio calculations have been carried out using the FP-APW+lo method in order to understand the atomic origin of the inverse piezoelectric effect in x-quartz. The external electric field was modelled by a saw-like potential V-ext in order to achieve translational symmetry within a supercell (SC) containing 72 atoms. The original trigonal quartz structure was repeated along the [110] direction, which corresponds to the direction of the external field. An electric field with 550 kV/mm was applied and the atomic positions of the SC were relaxed until the forces acting on the atoms vanished. In parts of the SC, V-ext changes almost linearly and thus the relaxed atomic positions can be used to determine the structural response due to the external electric field. The calculations provide the piezoelectric modulus of the correct order of magnitude. In contrast to previous models and in agreement with recent experimental results, the atomic origin of the piezoelectric effect can be described by a rotation of slightly deformed SiO4 tetrahedra against each other. The change of the Si-O bond lengths and the tetrahedral O-Si-O angles is one order of magnitude smaller than that of the Si-O-Si angles between neighbouring tetrahedra. The calculated changes of X-ray structure factors are in agreement with experiment when the theoretical data are extrapolated down to the much smaller field strength that is applied in the experiment (E < 10 kV/mm). (C) 2004 Elsevier Ltd. All rights reserved
allegro:1991-2014
10098914
Journal of Physics and Chemistry of Solids. - 65 (2004), S. 1967 - 1972
Ullrich Pietsch
Jav Davaasambuu
V. Kochin
K. H. Schwarz
Pawel Blaha
Institut für Physik und Astronomie
Referiert
Institut für Physik
16096
2003
2003
eng
article
1
--
--
--
Atomistic origin of the inverse piezoelectric effect in alpha-SiO2 and alpha-GaPO4
http://www.edpsciences.org/articles/epl/pdf/2003/12/7666.pdf?access=ok
0295-5075
allegro:1991-2014
10098894
Europhysics letters / the European Physical Society, EPS. - ISSN 0295-5075. - 62 (2003), 6, S. 834 - 840
Ullrich Pietsch
Jav Davaasambuu
Andreas Pucher
V. Kochin
Institut für Physik und Astronomie
Referiert
Institut für Physik
16218
2003
2003
eng
article
1
--
--
--
Double pinhole diffraction of white synchrotron radiation
allegro:1991-2014
10098891
Physica / b. - 336 (2003), 1-2, S. 63 - 67
Ullrich Pietsch
Wolfram Leitenberger
Horst Wendrock
Lothar Bischoff
Tobias Panzner
Jörg Grenzer
Andreas Pucher
Institut für Physik und Astronomie
Referiert
Institut für Physik
16472
2003
2003
eng
article
1
--
--
--
Evidence of a density grating under light induced formation of surface relief gratings at polymers containing azobenzene moieties
http://scitation.aip.org/getpdf/servlet/ GetPDFServlet?filetype=pdf&id=JAPIAU000094000002000963000001&idtype=cvips
allegro:1991-2014
10098885
Journal of applied physics. - 94 (2003), 2, S. 963 - 967
Ullrich Pietsch
Institut für Physik und Astronomie
Referiert
Institut für Physik
16484
2003
2003
eng
article
1
--
--
--
X-ray grazing-incidence study of inhomogeneous strain relaxation in Si/SiGe wires
0168-583X
allegro:1991-2014
10098908
Nuclear instruments and methods in physics research : Section B, Beam interactions with materials and atoms. - ISSN 0168-583X. - 200 C (2003), S. 267 - 272
Ullrich Pietsch
A. Hesse
Y. Zhuang
Vaclav Holý
Jochen Stangl
S. Zerlauth
F. Schaffler
Günther Bauer
Institut für Physik und Astronomie
Referiert
Institut für Physik
16455
2003
2003
eng
article
1
--
--
--
X-ray scattering amplitude of an atom in a permanent external electric field
allegro:1991-2014
10098907
Acta crystallographica / A. - 59 (2003), S. 221 - 227
Ullrich Pietsch
Vladimir G. Tsirelson
S. V. Gorfan
Institut für Physik und Astronomie
Referiert
Institut für Physik
16456
2003
2003
eng
article
1
--
--
--
Thermal diffuse scattering in grazing incidence diffraction
allegro:1991-2014
10098906
Journal of physics / c. - 15 (2003), 20, S. 3367 - 3374
Ullrich Pietsch
Souren A. Grigorian
Jörg Grenzer
Ivan A. Vartanyants
Institut für Physik und Astronomie
Referiert
Institut für Physik
16480
2003
2003
eng
article
1
--
--
--
Coherence experiments at the energy-dispersive reflectometry beamline at BESSY II
allegro:1991-2014
10098890
Journal of physics / d. - 36 (2003), 10a, S. 93 - 97
Ullrich Pietsch
Tobias Panzner
Wolfram Leitenberger
Jörg Grenzer
Th. Bodenthin
Thomas Geue
Helmuth Möhwald
Institut für Physik und Astronomie
Referiert
Institut für Physik
16481
2003
2003
eng
article
1
--
--
--
Grazing-incidence diffraction study of strain-modulated single quantum well nanostructures
allegro:1991-2014
10098892
Journal of physics / d. - 36 (2003), 10a, S. 222 - 224
Ullrich Pietsch
Souren A. Grigorian
Jörg Grenzer
S. Feranchuk
Ute Zeimer
Institut für Physik und Astronomie
Referiert
Institut für Physik
16482
2003
2003
eng
article
1
--
--
--
Energy dispersive x-ray reflectivity technique to study thermal properties of polymer films
allegro:1991-2014
10098909
Journal of applied physics. - 94 (2003), 5, S. 2882 - 2887
Ullrich Pietsch
M. K. Bhattacharya
M. Mukherjee
M. K. Sanyal
Thomas Geue
Jörg Grenzer
Institut für Physik und Astronomie
Referiert
Institut für Physik
16483
2003
2003
eng
article
1
--
--
--
Influence of lateral patterning geometry on lateral carrier confinement in strain-modulated InGaAs- nanostructures
allegro:1991-2014
10098905
Physica status solidi / A. - 195 (2003), 1, S. 178 - 182
Ullrich Pietsch
Ute Zeimer
Jörg Grenzer
Souren A. Grigorian
J. Fricke
S. Gramlich
F. Bugge
Markus Weyers
G. Trankle
Institut für Physik und Astronomie
Referiert
Open Access
Institut für Physik
16751
2002
2002
eng
article
1
--
--
--
Formation of a buried density grating on thermal erasure of azobenzene polymer surface gratings
0927-7757
allegro:1991-2014
10093304
Colloids and surfaces : an international journal devoted to the principles and applications of colloid and interface science / A. - ISSN 0927-7757. - Sp. Iss. - 198/200 (2002), S. 31 - 36
Thomas Geue
Oliver Henneberg
Jörg Grenzer
Ullrich Pietsch
Almeria Natansohn
Paul Rochon
Kenneth D. Finkelstein
Institut für Physik und Astronomie
Institut für Physik
16854
2002
2002
eng
article
1
--
--
--
Temperature and time resolved x-ray scattering at thin organic films
allegro:1991-2014
10093305
Journal of synchrotron radiation. - 9 (2002), 4, S. 206 - 209
Yves Bodenthin
Jörg Grenzer
Robert Lauter
Ullrich Pietsch
Pit Lehmann
Dirk G. Kurth
Helmuth Möhwald
Institut für Physik und Astronomie
Institut für Physik
16824
2002
2002
eng
article
1
--
--
--
X-ray reflectivity from sinusoidal surface relief gratings
0023-4753
allegro:1991-2014
10093307
Crystal research and technology : journal of experimental and industrial crystallography. - ISSN 0023-4753. - 37 (2002), 7, S. 770 - 776
Thomas Geue
Oliver Henneberg
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
30161
2009
2009
eng
article
1
--
--
--
Energy-dispersive Laue diffraction by means of a frame-store pnCCD
http://journals.iucr.org/j/journalhomepage.html
10.1107/S0021889809039867
0021-8898
allegro:1991-2014
10106060
Journal of applied crystallography. - ISSN 0021-8898. - 42 (2009), 6, S. 1139 - 1146
Sebastian Send
Marc von Kozierowski
Tobias Panzner
Semen Gorfman
Kivanc Nurdan
Albert H. Walenta
Ullrich Pietsch
Wolfram Leitenberger
Robert Hartmann
Lothar Strüder
Institut für Physik und Astronomie
32403
2007
2007
eng
article
1
--
--
--
Coherence experiments at the white-beam beamline of BESSYI
The third-generation X-ray source BESSYII (Berlin, Germany) provides coherent X-ray radiation which can be used for static and dynamic speckle analysis. Recently we have demonstrated that one can perform experiments with coherent white radiation provided by a bending magnet (5 < E < 20 keV). In this paper we show that the diffraction figure of the initial pinhole must be considered for the interpretation of coherent experiments. The reflectivity spectrum of a sample results from the Fresnel diffraction of the incident pinhole deformed by the static speckle features of the sample surface. For dynamical experiments all speckle like features alter with time whereas the pure Fresnel fringes remain constant. (c) 2007 Published by Elsevier B.V.
http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TW0-4N08M4P-1- F&_cdi=5548&_user=1584062&_orig=search&_coverDate=05%2F23%2F2007&_sk=994849985&view=c&wchp=dGLbVzW- zSkWA&md5=3a09375f874dccd9b382488e9d0
10.1016/j.tsf.2006.12.002
allegro:1991-2014
10103398
Thin Solid Films. - 515 (2007), 14, S. 5563 - 5567
Tobias Panzner
Gudrun Gleber
Tushar Sant
Wolfram Leitenberger
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
27686
1995
1995
eng
article
1
--
--
--
In-plane structure of uranylarachidate multilayers
allegro:1991-2014
10082289
Hamburger Synchrotronstrahlungslabor, HASYLAB : Jahresbericht, 1995. - Hamburg : DESY, 1995. - S. 249
Jürgen Reiche
Florencio Penacorada
Thomas Geue
Ullrich Pietsch
Ludwig Brehmer
Institut für Physik und Astronomie
Institut für Physik
25853
1996
1996
eng
article
1
--
--
--
Ab-initio Hartree-Fock study of the electronic charge density of the cubic boron nitride and its comparison with the experiment
allegro:1991-2014
10082234
Acta Crystallographica / B. - 52 (1996), S. 586 - 595
Albert Lichanot
P. Azavant
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
25857
1996
1996
eng
article
1
--
--
--
A critical review of the valence charge density in GaAs
allegro:1991-2014
10082278
Acta Crystallographica / B. - 52 (1996), S. 596 - 604
Ullrich Pietsch
N. K. Hansen
Institut für Physik und Astronomie
Institut für Physik
25863
1996
1996
eng
article
1
--
--
--
Accurate structure determination for GaAs using Pendellösung oscillation
allegro:1991-2014
10082318
German-Japanese Workshop on use of ultrashort wavelength photons and gamma rays for high-precision, high- resolution analysis of electronic states of solid. - Hamburg, 1996
Jochen Stahn
Marcus Möhle
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
29661
2007
2007
eng
article
1
--
--
--
Temperature dependent energy-dispersive X-ray diffraction and magnetic study of Fe/Al interface
In situ temperature dependent energy-dispersive structural and magnetic study of electron beam evaporated Fe/Al multilayer sample (MLS) has been investigated. The structural studies show the formation of an intermixed FeAl transition layer of a few nanometers thick at the interface during deposition, which on annealing at 300 degrees C transforms to B2FeAl intermetallic phase. Magnetization decreases with increase in temperature and drops to minimum above 300 degrees C due to increase in anti-ferromagnetic interlayer coupling and formation of nonmagnetic FeAl phase at the interface. The Curie temperature (T-c) is found to be 288 degrees C and is much less than that of bulk bcc Fe.
http://www.sciencedirect.com/science/journal/01694332
10.1016/j.apsusc.2007.04.069
0169-4332
allegro:1991-2014
10103405
Applied surface science. - ISSN 0169-4332. - 253 (2007), 21, S. 8584 - 8587
Ranjeet Brajpuriya
Sumit Tripathi
Abhishek Sharma
S.M. Chaudhari
D.M. Phase
Ajay Gupta
Thoudinja Shripathi
Wolfram Leitenberger
Ullrich Pietsch
N. Laxmi
Institut für Physik und Astronomie
Referiert
Institut für Physik
32319
2008
2008
eng
article
1
--
--
--
Application of a pnCCD in X-ray diffraction : a three-dimensional X-ray detector
The first application of a pnCCD detector for X-ray scattering experiments using white synchrotron radiation at BESSY II is presented. A Cd arachidate multilayer was investigated in reflection geometry within the energy range 7 keV < E < 35 keV. At fixed angle of incidence the two-dimensional diffraction pattern containing several multilayer Bragg peaks and respective diffuse-resonant Bragg sheets were observed. Since every pixel of the detector is able to determine the energy of every incoming photon with a resolution Delta E/E similar or equal to 10(-2). a three-dimensional dataset is finally obtained. In order to achieve this energy resolution the detector was operated in the so-called single-photon- counting mode. A full dataset was evaluated taking into account all photons recorded within 10(5) detector frames at a readout rate of 200 Hz. By representing the data in reciprocal-space coordinates, it becomes obvious that this experiment with the pnCCD detector provides the same information as that obtained by combining a large number of monochromatic scattering experiments using conventional area detectors.
http://onlinelibrary.wiley.com/iucr/10.1107/S0909049508018931
10.1107/S0909049508018931
allegro:1991-2014
10106144
Journal of synchrotron radiation. - 15 (2008), 5, S. 449 - 457
Wolfram Leitenberger
Robert Hartmann
Ullrich Pietsch
Robert Andritschke
Ines Starke
Lothar Strüder
Institut für Physik und Astronomie
Institut für Physik
24522
1997
1997
eng
article
1
--
--
--
The new reflectometer ADAM at the ILL
allegro:1991-2014
10087400
Physica / B. - 241 (1997), S. 169 - 171
R. Siebrecht
A. Schreyer
Uwe Englisch
Ullrich Pietsch
Hartmut Zabel
Institut für Physik und Astronomie
Institut für Physik
24526
1997
1997
eng
article
1
--
--
--
Characterization of lateral semiconductor nano structures by means of x-ray grazing-incidence diffraction
allegro:1991-2014
10087342
Applied physics letters. - 70 (1997), S. 1031
K. Paschke
Thomas Geue
Thomas Andreas Barberka
A. Bolm
Ullrich Pietsch
M. Rösch
Edwin Batke
F. Faller
K. Kerkel
J. Oshiniwo
Alfred Forchel
Institut für Physik und Astronomie
Institut für Physik
24527
1997
1997
eng
article
1
--
--
--
AFM and GID investigations of the gas-solid diazotation of 4-sulfanil-acid-monohydrat single crystals
allegro:1991-2014
10087345
Molecular crystals and liquid crystals. - 293 (1997), S. 261 - 275
A. Herrmann
G. Kaupp
Thomas Geue
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
24528
1997
1997
eng
article
1
--
--
--
Temperature and time dependent investigations of cd- and uranyl-stearate multilayers by means of neutron reflectivity measurements
allegro:1991-2014
10087347
Supramolecular science. - 4 (1997), S. 229
A. Bolm
Uwe Englisch
Florencio Penacorada
M. Gerstenberger
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
24529
1997
1997
eng
article
1
--
--
--
Characterization of InGaAs single quantum wells buried in GaAs[001] by grazing incidence diffraction
allegro:1991-2014
10087350
Journal of applied physics. - 81 (1997), S. 2601
Dirk Rose
Ullrich Pietsch
Ute Zeimer
Institut für Physik und Astronomie
Institut für Physik
24530
1997
1997
eng
article
1
--
--
--
Identification of a buried single quantum well within surface structurized semiconductors using depth resolved x-ray grazing-incidence diffraction
allegro:1991-2014
10087352
Journal of physics / D. - 30 (1997), L., S. 55 - 59
Nora Darowski
K. Paschke
Ullrich Pietsch
K. H. Wang
Alfred Forchel
Tilo Baumbach
Ute Zeimer
Institut für Physik und Astronomie
Institut für Physik
24532
1997
1997
eng
article
1
--
--
--
Thermally induced rearrangement of fatty acid salt molecules in Langmuir-Blodgett multilayers
allegro:1991-2014
10087357
Physica status solidi / B. - 201 (1997), S. 67 - 74
Uwe Englisch
T. Gutberlet
R. Seitz
R. Oeser
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
27777
1995
1995
eng
article
1
--
--
--
In-plane structure of perfluorotetra decanoic acid Langmuir-Blodgett films and films formed by vacuum deposition
allegro:1991-2014
10082288
Hamburger Synchrotronstrahlungslabor, HASYLAB : Jahresbericht, 1995. - Hamburg : DESY, 1995. - S. 247
Jürgen Reiche
Gerald Knochenhauer
Thomas Andreas Barberka
Thomas Geue
Ullrich Pietsch
Ludwig Brehmer
P. Hodge
Richard H. Tredgold
Institut für Physik und Astronomie
Institut für Physik
27778
1995
1995
eng
article
1
--
--
--
X-ray and neutron diffuse scattering from multilayers of fatty acid salt molecules
allegro:1991-2014
10082319
International Conference on Surface X-ray and Neutron Scattering, SXNS <4, 1995, Lake Geneva, Wisconsin>: proceedings of Fourth International Conference on Surface X-ray and Neutron Scattering / Hrsg.: G. P. Felcher ; H. You. - New York : Elsevier. - 1996. - S. 284 - 288
Ullrich Pietsch
Vaclav Holý
R. Strömmer
Uwe Englisch
Institut für Physik und Astronomie
Institut für Physik
27711
1995
1995
eng
article
1
--
--
--
Lateral structure of thermally treated oxadiazole Langmuir-Blodgett films
allegro:1991-2014
10082290
Hamburger Synchrotronstrahlungslabor, HASYLAB : Jahresbericht, 1995. - Hamburg, 1995. - S. 251
Jürgen Reiche
Birgit Dietzel
Anke-Christine Freydank
Thomas Geue
Ullrich Pietsch
Ludwig Brehmer
Institut für Physik und Astronomie
Institut für Physik
27699
1995
1995
eng
article
1
--
--
--
Investigation of the chain-chain interface in a lead-stearate multilayer using neutron reflectivity
allegro:1991-2014
10082184
Thin Solid Films. - 266 (1995), S. 234 - 237
Uwe Englisch
Thomas Andreas Barberka
Ullrich Pietsch
U. Höhne
Institut für Physik und Astronomie
Institut für Physik
27701
1995
1995
eng
article
1
--
--
--
Photochemically induced changes of optical anisotropy and surface of LB-multilayers built up by an amphiphilic and liquid crystalline copolymer conating azobenzene moieties
allegro:1991-2014
10082199
Molecular Crystals and Liquid Crystals. - 262 (1995), S. 157
Thomas Geue
Joachim Stumpe
Ullrich Pietsch
M. Haak
G. Kaupp
Institut für Physik und Astronomie
Institut für Physik
27693
1995
1995
deu
article
1
--
--
--
Neutronenreflektivität an Langmuir-Blodgett-Strukturen
allegro:1991-2014
10082185
Deutsche Physikalische Gesellschaft: Verhandlungen der DPG ; Reihe VI. - 30 (1995), 7, S. 1850
Uwe Englisch
Thomas Andreas Barberka
Ullrich Pietsch
U. Höhne
Jürgen Reiche
Birgit Dietzel
Institut für Physik und Astronomie
Institut für Physik
27851
1995
1995
deu
article
1
--
--
--
Diffuse Röntgenstreuung an LB-Filmen
allegro:1991-2014
10102391
Potsdamer Workshop Funktionalisierte Dünne Organische Schichten und Grenzflächen 22. - 24. Mai 1995 : abstracts / Hrsg.: Ludwig Brehmer. - Potsdam : Inst. für Festkörperphysik der Univ., 1995
Ralph Stömmer
Ute Zeimer
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
27833
1995
1995
deu
article
1
--
--
--
Phasentransformationen in Cd-Stearat-Multischichten bei unterschiedlichen Metallionenkonzentrationen
allegro:1991-2014
10102390
Potsdamer Workshop Funktionalisierte Dünne Organische Schichten und Grenzflächen 22. - 24. Mai 1995 : abstracts / Hrsg.: Ludwig Brehmer. - Potsdam : Inst. für Festkörperphysik der Univ., 1995
Willy Mahler
G. Bodenstein
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
27834
1995
1995
deu
article
1
--
--
--
Zeitaufgelöste Untersuchungen an Photochromen LB-Multischichten mittels energiedispersiver Röntgenkleinwinkelstreuung, in-plane Beugung und AFM
allegro:1991-2014
10102362
Potsdamer Workshop Funktionalisierte dünne organische Schichten und Grenzflächen, 22. - 24. Mai 1995 : Abstracts / Hrsg.: Ludwig Brehmer. - Potsdam : Inst. für Festkörperphysik der Univ., 1995
Th. Greue
Thomas Andreas Barberka
Ullrich Pietsch
Joachim Stumpe
G. Kauppe
Institut für Chemie
Institut für Physikalische Chemie und Theoretische Chemie
27835
1995
1995
deu
article
1
--
--
--
Neutronenreflektivität von teildeuterierten LB-Filmen mit verschiedenen Verhältnissen on protonierten zu deuterierten Schichten
allegro:1991-2014
10102360
Potsdamer Workshop Funktionalisierte dünne organische Schichten und Grenzflächen, 22. - 24. Mai 1995 : Abstracts / Hrsg.: Ludwig Brehmer. - Potsdam : Inst. für Festkörperphysik der Univ., 1995
Uwe Englisch
Ullrich Pietsch
Jürgen Reiche
Birgit Dietzel
Institut für Chemie
Institut für Physikalische Chemie und Theoretische Chemie
24004
1997
1997
eng
article
1
--
--
--
Energy dispersive X-ray reflectometry and X-ray grazing incidence diffraction from organic multilayers
allegro:1991-2014
10082260
International School and Symposium on Synchrotron Radiation in Natural Science <3 ; 1996, Jasowiec, Poland>: Proceedings of the 3rd International School and Symposium on Synchrotron Radiation in Natural Science : Jaszowiec, Poland, May 31 - June 8, 1996 / organized by Polish Synchrotron Radiation Society. Ed. of the proceedings: Jerzy Konior. Warsaw : Polish Academy of Sciences, Institute of Physics, 1997
Frank Neißendorfer
A. Bolm
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
28752
1994
1994
eng
article
1
--
--
--
Comprehensive structure investigation and computer modelling of perfluorododecanoic acid multilayers formed by in-vacuo thermal evaporation
allegro:1991-2014
10082284
Hamburger Synchrotronstrahlungslabor, HASYLAB : Jahresbericht, 1994. - Hamburg : DESY, 1994. - S. 407 - 408
Jürgen Reiche
Thomas Andreas Barberka
Gerald Knochenhauer
Martin Woolley
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
28741
1994
1994
eng
article
1
--
--
--
X-ray structure investigation and computer modelling of Langmuir-Blodgett films formed from disc-shaped pentaalkines
allegro:1991-2014
10082293
Hamburger Synchrotronstrahlungslabor, HASYLAB : Jahresbericht, 1994. - Hamburg : DESY, 1994. - S. 409 - 410
Jürgen Reiche
Thomas Andreas Barberka
Dietmar Janietz
Dieter Hofmann
Ullrich Pietsch
Ludwig Brehmer
Institut für Physik und Astronomie
Institut für Physik
29243
1992
1992
eng
article
1
--
--
--
A comparison fo x-ray methods for structure refinement of Langmuir-Blodgett multilayers
The possibilities and limits of structure refinement of Langmuir-Blodgett films by means of symmetrical reflection of X- rays are described using the example of a stearic acid multilayer. Three different techniques for the determiantion of the electron density profile from reflectivity data are compared; a Fourier method, a Patterson method, and model calculations. The important role of the a priori information for finding the besft structure model is outlined.
allegro:1991-2014
10084754
Acta Polymerica. - 43 (1992), S. 206 - 209
Jürgen Reiche
Ullrich Pietsch
Hans-Peter Fink
Helge Lemmetyinen
Institut für Physik und Astronomie
Institut für Physik
31872
2009
2009
eng
article
1
--
--
--
In situ and ex situ SAXS investigation of colloidal sedimentation onto laterally patterned support
We report on in situ investigations of colloidal ordering during gravity sedimentation from a colloidal suspension onto a prepatterned support using a polymeric surface relief grating (SRG) as the support. The ordering of colloids with a diameter of 420 nm was investigated by means of grazing-incidence small-angle X-ray scattering (GISAXS) and transmission SAXS using a preparation cell guaranteeing stable temperature and humidity. GISAXS was used for in situ monitoring of the time evolution of colloidal ordering within the whole illuminated sample area. The onset of ordering was indicated by the increase of integrated intensity within a small time frame shortly before complete evaporation of the dispersant. Single domains of coated samples were investigated ex situ by SAXS in transmission geometry where the irradiated sample area was 200 x 200 mu m(2) only. Domains with the typical size of a few millimeters were observed varying in orientation and crystallographic structure for various positions at the sample. They were mainly oriented along the grooves of the grating, confirming the influence of the underlying grating on colloidal ordering.
http://pubs.acs.org/journal/langd5
10.1021/La803078b
0743-7463
allegro:1991-2014
10108221
Langmuir. - ISSN 0743-7463. - 25 (2009), 2, S. 814 - 819
Beate Reinhold
Thomas Geue
Patrick Huber
Tushar Sant
Ullrich Pietsch
Michael Sztucki
Institut für Physik und Astronomie
Referiert
Open Access
31869
2009
2009
eng
article
1
--
--
--
In situ x-ray reflectivity and grazing incidence x-ray diffraction study of L1(0) ordering in Fe-57/Pt multilayers
In situ high temperature x-ray reflectivity and grazing incidence x-ray diffraction measurements in the energy dispersive mode are used to study the ordered face-centered tetragonal (fct) L1(0) phase formation in [Fe(19 angstrom)/ Pt(25 angstrom)](x10) multilayers prepared by ion beam sputtering. With the in situ x-ray measurements it is observed that (i) the multilayer structure first transforms to a disordered FePt and subsequently to an ordered fct L1(0) phase, (ii) the ordered fct L1(0) FePt peaks start to appear at 320°C annealing, (iii) the activation energy of the interdiffusion is 0.8 eV and (iv) ordered fct FePt grains have preferential out-of-plane texture. The magneto-optical Kerr effect and conversion electron Mossbauer spectroscopies are used to study the magnetic properties of the as- deposited and 400°C annealed multilayers. The magnetic data for the 400°C annealed sample indicate that the magnetization is at an angle of ~50° from the plane of the film.
http://iopscience.iop.org/0953-8984
10.1088/0953-8984/21/18/186002
0953-8984
allegro:1991-2014
10108218
Journal of physics : condensed matter. - ISSN 0953-8984. - 21 (2009), 18, Art. 186002
Raghavendra V. Reddy
Ajay Gupta
Anil Gome
Wolfram Leitenberger
Ullrich Pietsch
Institut für Physik und Astronomie
Referiert
24542
1997
1997
eng
article
1
--
--
--
X-ray scattering from thin organic films and multilayers
allegro:1991-2014
10087344
Il nuovo cimento della Societa Italiana di Fisica / D. - 19 (1997), 2/4, S. 393 - 402
Ullrich Pietsch
Thomas Andreas Barberka
Thomas Geue
Ralph Stömmer
Institut für Physik und Astronomie
Institut für Physik
23079
1998
1998
eng
article
1
--
--
--
Nondestructive analysis of a lateral GaAs nanostructure buried under AlGaAs using conventional high resolution and grazing incidence X-ray diffraction
allegro:1991-2014
10087374
Journal of applied physics. - 84 (1998), 3, S. 1366
Nora Darowski
Ullrich Pietsch
Ute Zeimer
V. Smirnitzki
F. Bugge
Institut für Physik und Astronomie
Institut für Physik
23080
1998
1998
eng
article
1
--
--
--
Comparative studies of fractal parameters of Si(100) surfaces measured by X-ray scattering and atomic force microscopy
allegro:1991-2014
10087375
Advances in X-ray analysis. - 41 (1998)
Ralph Stömmer
C. R. Martin
Thomas Geue
H. Göbel
W. Hub
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
23082
1998
1998
eng
article
1
--
--
--
X-ray scattering from silicon surfaces
allegro:1991-2014
10087392
Semiconductor international. - 1 (1998), S. 81 - 88
Ralph Stömmer
H. Göbel
W. Hub
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
23083
1998
1998
eng
article
1
--
--
--
In-plane strain and strain relaxation in laterally patterned Si/SiGe quantum dots and wire arrays
allegro:1991-2014
10087394
Applied physics letters. - 73 (1998), S. 806
Nora Darowski
Daniel Lübbert
Ullrich Pietsch
Y. Zhuang
S. Zerlauth
Günther Bauer
Institut für Physik und Astronomie
Open Access
Institut für Physik
23084
1998
1998
eng
article
1
--
--
--
Electric field induced electron density response of GaAs and ZnSe
allegro:1991-2014
10087398
Europhysics letters. - 44 (1998), 6, S. 714 - 720
Jochen Stahn
Andreas Pucher
Thomas Geue
A. Daniel
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
23085
1998
1998
eng
article
1
--
--
--
Influence of the deposition rate on the structure of thin metal layers
allegro:1991-2014
10087399
Thin solid films. - 318 (1998), S. 233
P. Haier
B. A. Herrmann
N. Esser
Ullrich Pietsch
K. Lüders
W. Richter
Institut für Physik und Astronomie
Institut für Physik
23086
1998
1998
eng
article
1
--
--
--
X-ray diffraction analysis of strain relaxation in free standing and buried GaAs/GaInAs/GaAs SQW lateral structures
allegro:1991-2014
10087407
Thin solid films. - 236 (1998), S. 271 - 276
Nora Darowski
Ullrich Pietsch
K. H. Wang
Alfred Forchel
W. Shen
S. Kycia
Institut für Physik und Astronomie
Institut für Physik
23069
1998
1998
eng
article
1
--
--
--
X-ray and transport characterization of an Esaki-Tsu superlattice device
allegro:1991-2014
10087354
Semiconductor science & technology. - 13 (1998), S. 733
Jörg Grenzer
E. Schomburg
I. Lingott
A. a. Ignotov
K. F. Renk
Ullrich Pietsch
Dirk Rose
Ute Zeimer
B. J. Melzer
S. Ivanov
S. Schaposchnikov
P. S. Kop'ev
D. G. Pavel'ev
Yu. Koschurinov
Institut für Physik und Astronomie
Institut für Physik
23076
1998
1998
eng
article
1
--
--
--
Investigation of strain relaxation in GaInAs/GaAs superlattices by x-ray diffuse scattering
allegro:1991-2014
10087370
Physica / B. - 248 (1998), S. 25
A. Ulyanenkov
U. Klemradt
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
23077
1998
1998
eng
article
1
--
--
--
Structural characterization of a GaAs surface wire structure by triple-axis X-ray grazing incidence diffraction
allegro:1991-2014
10087372
Physica / B. - 248 (1998), S. 104
Nora Darowski
K. Paschke
Ullrich Pietsch
K. H. Wang
Alfred Forchel
Daniel Lübbert
Tilo Baumbach
Institut für Physik und Astronomie
Institut für Physik
23060
1998
1998
eng
article
1
--
--
--
Investigation of the vertical molecular exchange in a complex organic multilayer system
allegro:1991-2014
10087371
Physica / B. - 248 (1998), S. 258
Uwe Englisch
Florencio Penacorada
I. Samoilenko
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
23066
1998
1998
eng
article
1
--
--
--
Critical pionts in a crystal an procrystal
allegro:1991-2014
10087351
Structural chemistry. - 9 (1998), 4, S. 249 - 254
Vladimir G. Tsirelson
Yury Fedorovich Abramov
Valerie E. Zavodnik
Adam I. Stash
Elena L. Belokoneva
Jochen Stahn
Ullrich Pietsch
Dirk Feil
Institut für Physik und Astronomie
Referiert
Institut für Physik
23068
1998
1998
eng
article
1
--
--
--
Comparison of theoretical and experimental structure amplitudes of GaAs
allegro:1991-2014
10087353
Acta crystallographica / B. - 54 (1998), S. 231 - 239
Jochen Stahn
Marcus Möhle
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
24916
1997
1997
eng
article
1
--
--
--
Monolayers and multilayers of uranyl arachidate : in-plane structure of uranyl arachidate multilayers
The molecular in-plane structure of uranyl arachidate Langmuir-Blodgett (LB) films formed at different subphase pH values was analysed by means of X-ray grazing-incidence diffraction. For multilayers formed at low subphase pH a reorganisation of the arachidic acid film structure is confirmed. At appropriate subphase pH values, reorganisation of the film structure, e.g. via the formation of three-dimensional crystallites, is prevented by the presence of the uranyl ions and by the subsequent introduction of conformational disorder (gauche defects) in the alkyl chains. The observation of a macroscopic flow-induced in-plane texture in these uranyl arachidate LB films has profound implications for the design of ordered, supramolecular structures by the Langmuir-Blodgett technique.
allegro:1991-2014
10084864
Supramolecular Science. - 4 (1997), S. 559 - 563
Jürgen Reiche
Florencio Penacorada
Thomas Geue
Ullrich Pietsch
Ludwig Brehmer
Institut für Physik und Astronomie
Institut für Physik
24917
1997
1997
eng
article
1
--
--
--
Structure of thermally treated oxadiazoleamide Langmuir-Blodgett films
The thermal treatment of Y-type Langmuir-Blodgett (LB) films formed from the amphiphilic derivative of 2,5- diphenyl-1,3,4-oxadiazole 1 results in changes of the molecular packing. These changes have been analysed by a combination of X-ray specular reflectivity data, X-ray grazing incidence diffraction data and scanning force microscopy images, On the basis of these experimental data we have simulated possible supramolecular structures, These simulations provide insight into the intermolecular interactions giving rise to the observed structural transitions. The crystalline structure induced by thermal treatment of the LB films is characterized by a uniaxial texture, which is correlated with the dipping direction during deposition of the LB film.
allegro:1991-2014
10085399
Supramolecular science. - 4 (1997), S. 455 - 459
Jürgen Reiche
Gerald Knochenhauer
Reinhard Dietel
Anke-Christine Freydank
Thomas Zetzsche
Ullrich Pietsch
Ludwig Brehmer
Thomas Andreas Barberka
Thomas Geue
Institut für Physik und Astronomie
Institut für Physik
30403
1999
1999
eng
article
1
--
--
--
Scanning system for high-energy electron diffractometry
http://www3.interscience.wiley.com/journal/118518709/home?CRETRY=1&SRETRY=0
10.1107/S0021889899006755
0021-8898
allegro:1991-2014
10087406
Journal of applied crystallography. - ISSN 0021-8898. - 32 (1999), 6, S. 1033 - 1038
Anatoly S. Avilov
Alexander K. Kulygin
Ullrich Pietsch
John C. H. Spence
Vladimir G. Tsirelson
Ming J. Zuo
Institut für Physik und Astronomie
Referiert
Institut für Physik
31420
2006
2006
eng
article
1
--
--
--
Simultaneous X-ray and visible light diffraction for the investigation of surface relief and density grating formation in azobenzene containing polymer films
The development of surface relief and density patterns in azobenzene polymer films was studied by diffraction at two different wavelengths. We used x-ray diffraction of synchrotron radiation at 0.124 nm in combination with visible light diffraction at a wavelength of 633 nm. In contrast to visible light scattering x-ray diffraction allows the separation of a surface relief and a density grating contribution due to the different functional dependence of the scattering power. Additionally, the x-ray probe is most sensitive for the onset of the surface grating formation
http://www.informaworld.com/smpp/title~content=t713644168~db=all
10.1080/15421400500383345
1542-1406
allegro:1991-2014
10102109
Molecular crystals and liquid crystals. - ISSN 1542-1406. - 446 (2006), S. 111 - 121
Oliver Henneberg
Ullrich Pietsch
Tobias Panzner
Thomas Geue
Kenneth D. Finkelstein
Institut für Physik und Astronomie
Referiert
Institut für Physik
35000
2013
2013
eng
132
142
11
5
711
article
Elsevier
Amsterdam
1
--
--
--
Characterization of a pnCCD for applications with synchrotron radiation
In this work we study the response of a pnCCD by means of X-ray spectroscopy in the energy range between 6 key and 20 key and by Laue diffraction techniques. The analyses include measurements of characteristic detector parameters like energy resolution, count rate capability and effects of different gain settings. The limit of a single photon counting operation in white beam X-ray diffraction experiments is discussed with regard to the occurrence of pile-up events, for which the energy information about individual photons is lost. In case of monochromatic illumination the pnCCD can be used as a fast conventional CCD with a charge handling capacity (CHC) of about 300,000 electrons per pixel. If the CHC is exceeded, any surplus charge will spill to neighboring pixels perpendicular to the transfer direction due to electrostatic repulsion. The possibilities of increasing the number of storable electrons are investigated for different voltage settings by exposing a single pixel with X-rays generated by a microfocus X-ray source. The pixel binning mode is tested as an alternative approach that enables a pnCCD operation with significantly shorter readout times.
Nuclear instruments & methods in physics research : a journal on accelerators, instrumentation and techniques applied to research in nuclear and atomic physics, materials science and related fields in physics ; A, Accelerators, spectrometers, detectors and associated equipment
10.1016/j.nima.2013.01.044
0168-9002
wos:2011-2013
WOS:000318321300018
Send, S (reprint author), Univ Siegen, Dept Phys, Walter Flex Str 3, D-57068 Siegen, Germany., send@physik.uni-siegen.de
BMBF Verbundforschung [05K10PSB]
Sebastian Send
Ali Abboud
Robert Hartmann
M. Huth
Wolfram Leitenberger
N. Pashniak
J. Schmidt
Lothar Strüder
Ullrich Pietsch
eng
uncontrolled
pnCCD
eng
uncontrolled
X-ray spectroscopy
eng
uncontrolled
X-ray imaging
eng
uncontrolled
Energy-dispersive Laue diffraction
Institut für Physik und Astronomie
Referiert
35860
2012
2012
eng
517
522
6
6
45
article
Wiley-Blackwell
Hoboken
1
--
--
--
Analysis of polycrystallinity in hen egg-white lysozyme using a pnCCD
A crystal of hen egg-white lysozyme was analyzed by means of energy-dispersive X-ray Laue diffraction with white synchrotron radiation at 2.7 angstrom resolution using a pnCCD detector. From Laue spots measured in a single exposure of the arbitrarily oriented crystal, the lattice constants of the tetragonal unit cell could be extracted with an accuracy of about 2.5%. Scanning across the sample surface, Laue images with split reflections were recorded at various positions. The corresponding diffraction patterns were generated by two crystalline domains with a tilt of about 1 degrees relative to each other. The obtained results demonstrate the potential of the pnCCD for fast X-ray screening of crystals of macromolecules or proteins prior to conventional X-ray structure analysis. The described experiment can be automatized to quantitatively characterize imperfect single crystals or polycrystals.
Journal of applied crystallography
10.1107/S0021889812015038
0021-8898
wos:2011-2013
WOS:000304402500019
Send, S (reprint author), Univ Siegen, Dept Phys, D-57068 Siegen, Germany., send@physik.uni-siegen.de
BMBF Verbundforschung [05K10PSB]
Sebastian Send
Ali Abboud
Wolfram Leitenberger
Manfred S. Weiss
Robert Hartmann
Lothar Strüder
Ullrich Pietsch
Institut für Physik und Astronomie
Referiert
17630
2002
2002
eng
article
1
--
--
--
X-ray reflectivity from sinusoidal surface relief gratings
allegro:1991-2014
10098887
Physical Review / e. - 66 (2002), S. 155430
Ullrich Pietsch
Institut für Physik und Astronomie
Referiert
Institut für Physik
17631
2002
2002
eng
article
1
--
--
--
Reversible negative thermal expansion of polymer films
allegro:1991-2014
10098888
Physical Review / e. - 66 (2002), 6 , Art. Nr. 061801
Ullrich Pietsch
Institut für Physik und Astronomie
Referiert
Institut für Physik
18193
2001
2001
eng
article
1
--
--
--
X-ray reflectivity analysis of thin complex Langmuir-Blodgett films
allegro:1991-2014
10093150
Journal of physics / D. - 34 (2001) 4, S. 450 - 458
P. Poloucek
Ullrich Pietsch
Thomas Geue
Christian Symietz
Gerald Brezesinski
Institut für Physik und Astronomie
Institut für Physik
18197
2001
2001
eng
article
1
--
--
--
Electric field induced charge-density variations in covalently bonded compounds
allegro:1991-2014
10093146
Physical review / B. - 65 (2001), Art.-Nr. 165205
Jochen Stahn
Ullrich Pietsch
Pawel Blaha
K. H. Schwarz
Institut für Physik und Astronomie
Institut für Physik
18158
2001
2001
eng
article
1
--
--
--
Electric field induced charge density variations in partially-ionic compounds
0022-3697
allegro:1991-2014
10093288
The journal of physics and chemistry of solids : JPCS ; an international journal. - ISSN 0022-3697. - 62 (2001), 12, S. 2129 - 2133
Ullrich Pietsch
Jochen Stahn
Jav Davaasambuu
Andreas Pucher
Institut für Physik und Astronomie
Institut für Physik
18251
2001
2001
eng
article
1
--
--
--
Harmonic and anharmonic thermal vibrations in cubic ZnSe
0044-2968
allegro:1991-2014
10093144
Zeitschrift für Kristallographie : internat. journal for structural, physical, and chemical aspects of crystalline materials. - ISSN 0044-2968. - 216 (2001), 1, S. 22 - 25
Jav Davaasambuu
A. Daniel
Jochen Stahn
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
18253
2001
2001
eng
article
1
--
--
--
Strain induced compositional modulations in AlGaAs overlayers induced by lateral surface gratings
0272-9172
allegro:1991-2014
10093148
Materials Research Society symposium proceedings. - ISSN 0272-9172. - 618 (2001), S. 41 - 46
Ullrich Pietsch
Ute Zeimer
L. Hofmann
Jörg Grenzer
S. Gramlich
Institut für Physik und Astronomie
Institut für Physik
18269
2001
2001
eng
article
1
--
--
--
Comparison of experimental and theoretical valence charge densites in cubic ZnSe
0022-3697
allegro:1991-2014
10093289
The journal of physics and chemistry of solids : JPCS ; an international journal. - ISSN 0022-3697. - 62 (2001), 12 , S. 2147 - 2152
Jav Davaasambuu
A. Daniel
Jochen Stahn
Ullrich Pietsch
Institut für Physik und Astronomie
Institut für Physik
18270
2001
2001
eng
article
1
--
--
--
Multipole analysis of the electron density and electrostatic potential in Germanium by high-resolution electron diffraction
0022-3697
allegro:1991-2014
10093290
The journal of physics and chemistry of solids : JPCS ; an international journal. - ISSN 0022-3697. - 62 (2001), 12, S. 2135 - 2142
Anatoly S. Avilov
G. G. Lepeshov
Ullrich Pietsch
Vladimir G. Tsirelson
Institut für Physik und Astronomie
Institut für Physik