A5023733703- Surface Roughness and Optical Measurements
- Semiconductor Quantum Structures and Devices
- Electron and X-Ray Spectroscopy Techniques
- Liquid Crystal Research Advancements
- Ion-surface interactions and analysis
- Photonic and Optical Devices
- Integrated Circuits and Semiconductor Failure Analysis
- Advanced Materials and Mechanics
- Magnetic Field Sensors Techniques
- Crystallography and Radiation Phenomena
- Biosensors and Analytical Detection
- Advanced Materials Characterization Techniques
- Metallic Glasses and Amorphous Alloys
- Photonic Crystals and Applications
- Radiation Effects in Electronics
- Optical Coatings and Gratings
- Physics of Superconductivity and Magnetism
- Analytical chemistry methods development
- Molecular spectroscopy and chirality
- Force Microscopy Techniques and Applications
- Surface and Thin Film Phenomena
- Advanced Semiconductor Detectors and Materials
- Magnetic properties of thin films
- Optical and Acousto-Optic Technologies
- Characterization and Applications of Magnetic Nanoparticles
Federal Institute for Risk Assessment
2023
Humboldt-Universität zu Berlin
1997-2001
Institute for Atomic and Molecular Physics
2000-2001
Paul Drude Institute for Solid State Electronics
1999
Max Planck Society
1997
Entwicklungszentrum für Schiffstechnik und Transportsysteme
1997
Lomonosov Moscow State University
1996
Deggendorf Institute of Technology
1990
Paderborn University
1988
The x-ray scattering from relaxed heteroepitaxial layers with the misfit dislocations randomly distributed at interface between layer and substrate is analyzed theoretically experimentally. profiles of x-ray-diffraction peaks reciprocal space maps intensity are measured simulated for several structures in a wide range dislocation densities. At large densities, peak position governed by mean distortions width due to mean-square variations distortions. widths calculated uncorrelated...
The features of surface and interface roughness in crystalline AlAs/GaAs superlattices grown by molecular beam epitaxy on vicinal (001) GaAs substrates are studied grazing-incidence x-ray scattering (GIXS). effects different growth modes [step-flow or two-dimensional- (2D-) nucleation], substrate preparations, interruptions the investigated. results GIXS compared with atomic force microscopy (AFM) images sample surfaces. For samples step-flow mode, both methods display a distinct anisotropy...
Collinear acoustooptic TM-TE mode conversion is experimentally investigated in proton exchanged Ti:LiNbO/sub 3/ optical waveguides. Their birefringence adjusted by an appropriate annealing to allow phase matching at surface acoustic wave frequencies of about 90 MHz and 180 MHz, respectively. A planar converter with efficiency up percent presented (87 175 MHz). Furthermore, a combined acoustical/optical strip waveguide structure developed as converter, leading strongly reduced power...
We report on a combined x-ray reflectivity and optical ellipsometry study of freely suspended smectic (Sm) films chiral liquid crystalline compound with the phase sequence $\mathrm{Sm}\ensuremath{-}A--{\mathrm{S}\mathrm{m}\ensuremath{-}\mathrm{C}}_{\ensuremath{\alpha}}^{*}--{\mathrm{S}\mathrm{m}\ensuremath{-}\mathrm{C}}^{*}--{\mathrm{S}\mathrm{m}\ensuremath{-}\mathrm{C}}_{\ensuremath{\gamma}}^{*}--{\mathrm{S}\mathrm{m}\ensuremath{-}\mathrm{C}}_{A}^{*}.$ Using tilt magnitude profiles from as...
Due to the extremely high specific surface area of nanoparticles and corresponding potential for adsorption, results analysis can be highly dependent on history particles, particularly regarding sample preparation storage. The method has, therefore, have a significant influence results. This report describes an interlaboratory comparison (ILC) with aim assessing which methods ToF-SIMS provided most intra- consistency least amount contamination. BAM reference material BAM-P110 (TiO2 mean...
The peculiarities of high-resolution measurements in grazing-incidence diffraction (GID) are studied, both theoretically and experimentally. It is shown that complete discrimination between coherent reflection diffuse scattering due to defects GID requires a three-dimensional mapping reciprocal space. These can be performed using combination analyzer crystal position-sensitive detector for angular analysis scattered x-rays mutually perpendicular planes. equations the resolution function...
The inclined inheritance of interface roughness is investigated for an AlAs/GaAs superlattice grown by molecular beam epitaxy on a vicinal (001) GaAs substrate. As consequence vertical correlation the subsequent interfaces diffusely scattered x-ray intensity bunched into resonant diffuse scattering (RDS) sheets in reciprocal space. Inclined leads to corresponding shearing RDS sheets. A simple model evaluation three dimensions presented, where sheared are modeled anisotropic ellipsoids. From...
Characteristics of the interface roughness in a low-pressure organometallic vapour phase epitaxy (LPOMVPE) grown AlAs/GaAs multilayer are studied by grazing-incidence x-ray scattering. Quantitative results obtained comparing experimental and theoretically calculated diffuse scattering maps. These corroborate with features resolved atomic force microscopy. The observed morphological discussed following sections.
Abstract According to a central composite design samples with deviations from stoichiometry YBa 2 Cu 3 O 7− x of ±2.5 wt% in the ingredients were prepared. The influence these on phase content, superconducting properties and microstructure ceramics was studied.