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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
Grazing-incidence X-ray diffraction measurements on single GaAs nanowires (NWs) grown on a (111)-oriented GaAs substrate by molecular beam epitaxy are reported. The positions of the NWs are intentionally determined by a direct implantation of Au with focused ion beams. This controlled arrangement in combination with a nanofocused X-ray beam allows the in-plane lattice parameter of single NWs to be
We have built a new small furnace to perform high temperature studies up to 1200°C in vacuum or in oxygen atmosphere. This furnace was originally used as a catalytic reactor optimized for the in situ X-ray Absorption Spectroscopy experiments on beamline ID24. It has now been redesigned for use on the ESRF beamline ID01 for in situ Grazing Incidence Small Angle X-ray Scattering experiments. For the
The properties of nanoscale materials vary with the size and shape of the building blocks, which can be measured by (grazing-incidence) small-angle X-ray scattering along with the mutual positions of the nanoparticles. The accuracy in the determination of such parameters is dependent on the signal-to-noise ratio of the X-ray scattering pattern and on the visibility of the interference fringes. Her
Radiocarbon (14C), as a consequence of its production in the atmosphere and subsequent dispersal through the carbon cycle, is a key tracer for studying the Earth system. Knowledge of past 14C levels improves our understanding of climate processes, the Sun, the geodynamo, and the carbon cycle. Recently updated radiocarbon calibration curves (IntCal20, SHCal20, and Marine20) provide unprecedented ac
The 2015 Paris Agreement specified that the goal of international climate policy is to strengthen the global response to climate change by restricting the average global warming this century to “well below” 2°C above pre-industrial levels and to pursue efforts to limit it to 1.5°C. In this context, “Negative Emissions Technologies” (NETs)—technologies that remove additional greenhouse gases (GHGs)
We investigated the growth of CdS nanoparticles in polymer films by means of ex-situ and in-situ x-ray scattering experiments using synchrotron radiation. The CdS nanoparticles were synthesized by thermal decomposition of a Cd thiolate precursor dispersed in a cyclic olefin copolymer. The films were deposited by spin coating. Grazing incidence diffraction (GID) reveals the Bragg reflections of the
There is currently interest in low strain HPHT diamond due to its expected application as various types of X-ray optical elements at Synchrotrons, where the X-ray intensity is becoming progressively too severe for the existing materials. The diamond crystals need to be synthesised with unprecedented lattice quality. In recent measurements at the ID19 beamline of European Synchrotron Radiation Faci
We describe in this paper the performance under synchrotron radiation of a sealed gaseous detector, Vantec-1, operating at high pressure and less prone to discharges. It is consequently operating at high gain (>105) at high local counting rates up to 106 cps/mm2. To achieve these characteristics, a thin resistive layer is used on a glass plate between the mesh and the readout anode. The performanc
Structural and transport properties of (Bi2Sr2CuO6+δ)m/(CaCuO 2)n superconducting multilayers, obtained by molecular beam epitaxy (MBE) alternately stacking m layers of Bi2Sr2CuO6+δ with n layers of CaCuO2, have been studied. Resistivity measurements and I-V characteristics in perpendicular and parallel magnetic fields have allowed to estimate the anisotropy parameter which results very low with r
High quality single-crystal synthetic diamond is the most suitable material for selected X-ray optical applications in the latest generation X-ray light sources. Excellent heat handling properties, as well as low absorption, coupled with high perfection in the crystal bulk and very good surface quality, are crucial for such applications. In recent years, some progress has been made in the fields o
High temperature superconducting multilayers have been obtained depositing Bi2Sr2CuO6+δ (2201) and ACuO2 layers, where A is C a or Sr, by Molecular Beam Epitaxy (MBE) on M gO and SrTiO3 substrates. The samples, formed by a sequence of 2201/ACuO2 bilayers,
Resistivity measurements in external applied magnetic field up to 8.5T have been performed on Bi2Sr2CuO6+δ/CaCuO2 superconducting superlattices obtained by MBE. The magnetic field (H) vs. temperature (T) phase diagrams have been determined and the experimental data have been compared with that obtained in the case of Bi2Sr2CuO6+δ thin films deposited with the same technique. A reduction of the ani
Bi-based high temperature superconduting multilayers have been obtained by Molecular Beam Epitaxy (MBE) using a deposition method which consists of both co-deposition and growth interruption techniques. We have studied two kinds of structures in which a layer of BizSrzCuOg+s (2201) is alternately stacked by an insulating layer of CaCuOi or SrCuOi in order to obtain 2201/CaCuO2 or IWl/SrCuO?. multi
Optical DNA mapping (ODM) is based on fluorescent labeling, stretching and imaging of single DNA molecules to obtain sequence-specific fluorescence profiles, DNA barcodes. These barcodes can be mapped to theoretical counterparts obtained from DNA reference sequences, which in turn allow for DNA identification in complex samples and for detecting structural changes in individual DNA molecules. Ther
Bi-based superconducting multilayers, consisting of Bi2Sr2CuO6+δ (2201) layers alternately stacked with CaCuO2 or SrCuO2 layers, have been deposited by Molecular Beam Epitaxy (MBE) using co-deposition and growth interruption techniques. In situ Reflection High Energy Electron Diffraction (RHEED) has been used to monitor the surface of the different layers giving evidence of a two-dimensional growt
Growth of AlGaInAs/InP heterostructures by Selective Area Metal Organic Vapour Phase Epitaxy is investigated in this paper using advanced characterization techniques and numerical modelling. Synchrotron radiation and X-Ray optics allow to have micro or sub-micro X-Ray probe. With this probe, it is possible to characterize our samples by X-Ray Diffraction on very restricted area. This technique was
