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Due to the complex interplay of magnetic, structural, electronic, and orbital degrees of freedom, biaxial strain is known to play an essential role in the doped manganites. For coherently strained La2/3Ca1/3MnO3 thin films grown on SrTiO3 substrates, we measured the magnetotransport properties both parallel and perpendicular to the substrate and found an anomaly of the electrical transport propert
We report on the preparation of high performance field-effect transistors (FETs) based on large areas of aligned films of a TTF derivative, namely, tetrakis-(octadecylthio)-tetrathiafulvalene (TTF-4SC18). TTF-4SC18 assembles into one-dimensional stacks in which the long alkyl chains promote intermolecular π-π overlapping due to their extremely closely packed nature. The films were prepared from so
X-ray absorption and magnetic circular dichroism spectra of as-deposited and postannealed Fe50 Pt50 /C granular multilayers were measured at both the Fe and Pt L2,3 edges. We demonstrate that the partial L 10 ordering of the FePt nanoparticles induced by thermal annealing results in an increase of the effective spin magnetic moments by 200% at the Fe site and by 65% at the Pt site, while the orbit
We present a study of the early stage of ripple formation on Ge(001) surfaces irradiated by a 1 keV Xe+ ion beam at room temperature and near-normal incidence. A combination of a grazing incidence x-ray scattering technique and atomic force microscopy allowed us to observe a variation of the symmetry of the surface nanopattern upon increase of the ion fluence. The isotropic dot pattern formed duri
Silicon and Teflon substrates have been structured by wet etching and a focused ion beam (FIB) to obtain very defined, clean apertures. Planar, free-standing lipid membranes (black lipid membranes (BLM)) with enhanced long-term stability have been prepared on these apertures by the methods of Montal and Müller1.2 as well as Müller and Rudin. 3 The stability and geometric control enables the use of
This work is focused on synthesis, characterization, and determination of main parameters of the multilayer P123 templated TiO2 films. The mesoporous multilayer thin films consist of TiO2 nanoparticles on the F-doped SnO2 (FTO) conductive glass substrates. The films were grown by implementing the protocol of supramolecular templating with the amphiphilic triblock copolymer, Pluronic P123. The temp
A compact portable vacuum-compatible chamber designed for surface X-ray scattering measurements on beamline ID01 of the European Synchrotron Radiation Facility, Grenoble, is described. The chamber is versatile and can be used for in situ investigation of various systems, such as surfaces, nanostructures, thin films etc., using a variety of X-ray-based techniques such as reflectivity, grazing-incid
We report on periodic ripple formation on Si(001) surfaces after bombardment with Xe+ ions with energies between 5 and 35 keV under incidence angles of 65° and 70°. The sputter process leads to the formation of a rippled amorphous surface layer, followed by a rippled interface toward crystalline material. Using grazing-incidence small-angle scattering and diffraction, we show that the surface morp
Amyloid fibrils are associated with a number of neurodegenerative diseases, including fibrils of amyloid β42 peptide (Aβ42) in Alzheimer's disease. These fibrils are a source of toxicity to neuronal cells through surface-catalyzed generation of toxic oligomers. Detailed knowledge of the fibril structure may thus facilitate therapeutic development. We use small-angle scattering to provide informati
TiO2(B) mesoporous thin films were grown in two steps on the F-doped SnO2 conductive glass substrates. In the first step, a small amount of H3PO4, corresponding to 0.15-0.375 wt % P on TiO2 basis, was introduced into concentrated HCl which was subsequently used for hydrolysis of titanium ethoxide. The hydrolyzed colloidal TiO2 suspension was further mixed with a 1-butanol solution of the amphiphil
During ion sputtering of GaSb(100) surfaces a transient behavior from initial smoothing to roughening accompanied by self-organized pattern formation has been observed using in situ x-ray reflectivity and grazing incidence small angle scattering. The induced patterns show hexagonally ordered nanodot arrays with a spatial periodicity of 30 nm. The correlation length of the pattern increases with io
We demonstrate an X-ray coherent imaging method that combines high spatial resolution with the ability to map grains within thick polycrystalline specimens. An X-ray objective serves to isolate an embedded grain. Iterative oversampling routines and Fourier synthesis are used to reconstruct the shape and strain field from the far-field intensity pattern. In a demonstration experiment a ∼500-nm Pt g
The 2015 Paris Agreement aims to strengthen the global response to climate change, and to maintain an average global temperature well below 2°C, with aspirations toward 1.5°C, by means of balancing sources and sinks of greenhouse gas emissions. Following this, the importance of carbon dioxide removal in global emission pathways has been further emphasized, and Negative Emissions Technologies (NETs
In this work, we describe the synthesis of CdS nanocrystals in thin polymeric films by in-situ Grazing Incidence Diffraction (GID) and Grazing Incidence Small Angle Scattering (GISAXS). The 2D GISAXS patterns indicate how the precursor structure is altered as the temperature is varied from 25°C to 300°C. At 150°C, the CdS nanocrystals start to arrange themselves in a hexagonal lattice with a latti
Hard X-ray lens-less microscopy raises hopes for a non-invasive quantitative imaging, capable of achieving the extreme resolving power demands of nanoscience. However, a limit imposed by the partial coherence of third generation synchrotron sources restricts the sample size to the micrometer range. Recently, X-ray ptychography has been demonstrated as a solution for arbitrarily extending the field
The possibility to investigate complex magnetic profiles throughout an ultrathin magnetic film or an interface by soft x-ray resonant magnetic reflectivity is presented. The determination of in- and out-of-plane magnetic profile is shown to be possible with a subnanometer resolution by measuring the reflectivity over a wide angular range. The technique is applied to a granular magnetic multilayer
Polymers such as benzocyclobutene are commonly used as embedding materials for semiconductor nanostructures. During the curing process of the polymer up to 250 °C, a significant impact of strain can be induced on the embedded semiconductor material due to different thermal expansion coefficients. This strain has been revealed by X-ray diffraction in free-standing GaAs nanowires grown on a silicon
In this work, selective area growth has been used for the realization of InP based photonic integrated circuits (PICs). To predict the strain, thickness and bandgap energy variations over large and high-density multifunctional arrays, it is necessary to precisely design the shapes and positions of the dielectric masks by computational modeling. To address the mask layout density and complexity in
Parental care can be partitioned into traits that involve direct engagement with offspring and traits that are expressed as an extended phenotype and influence the developmental environment, such as constructing a nursery. Here, we use experimental evolution to test whether parents can evolve modifications in nursery construction when they are experimentally prevented from supplying care directly
This paper reports the latest improvements performed on structural characterization by high resolution x-ray diffraction (XRD) on InGaAlAs-based multiple quantum well (MQW) structures on InP substrates, produced by metal organic vapor phase epitaxy in the regime of selective area growth (SAG). A new diffractometer, with a sub-millimeter x-ray spot, was used in the laboratory to study the MQW prope
