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Single-ion implantation as a technique for fabricating future quantum devices requires high precision in placing individual ions in the semiconductor material. One way to achieve this precision is to use focused ion beams and verify the implantation of each ion by detecting the charge it induces in the semiconductor. This method has already been demonstrated for silicon substrates but has yet to be successfully performed for wide-bandgap materials. One of the most promising materials for future quantum devices is a diamond. Quantum centers in diamond, such as nitrogen vacancies, can serve as information carriers in quantum computers—qubits— and are stable at room temperature. This work focuses on understanding the critical parameters required for the successful detection of shallow, low-energy ions in diamonds using commercially available diamond crystals and front-end electronics. Depth profiling of the electric field in the diamond crystal was performed using ions of different species and energy. State-of-the-art front-end electronics were also used to achieve high energy resolution. Using the XGLab CUBE PRE031 preamplifier, an energy resolution of 6 keV was achieved for the detection of 400-keV protons. Detection of 140-keV copper ions, penetrating an average of 100 nm into the diamond, was also demonstrated. The optimal position of implantation sites was determined from the spatial distribution of charge collection efficiency.

The Environmental Monitoring Units (EMU), on-board two satellites of the EU Galileo constellation, monitor the radiation environment along the GNSS orbit providing measurements of the energetic electron fluxes in the outer Van Allen Belt. With new calibration studies that take into account more realistic shielding provided by the spacecraft and the characteristics of the encountered environment along the satellite orbit, we have derived a new version of the GSAT/EMU Level 1 dataset that provides high quality validated fluxes of trapped energetic electrons within the 0.2-4.5 MeV energy range. In this work, we present an overview of the EMU measured electron fluxes over the last five years including recently completed validation studies with Arase [ERG] and RBSP energetic electron measurements. The new dataset, available to users from European member states registered at https://gssc.esa.int, will be used in the assimilation processes and/or the validation of the ONERA Salammbô electron radiation belt models - under the EU Safespace activity and ESA S2P RBFAN activity - leading to improved forecasts of the state of the outer belt. In addition, the quality of the time-coverage of the dataset permits their use in the development and/or evaluation of quantitative radiation environment specification models. This work has received funding from the European Union’s Horizon 2020 research and innovation programme "SafeSpace" under grant agreement No 870437, from the European Space Agency activity "Cross Calibration EMU Dataset with RBSP" under ESA Contract 4000135823/21/NL/GLC/mkn and the “SSA P3-SWE-X Space Environment Nowcast and Forecast Development” activity under ESA Contract 4000131381/20/D/CT.

Pure Ti films deposited by radio-frequency magnetron sputtering on FTO glass were anodized to fabricate TiO2 nanotubes (NTs) arrays. The TiO2 NTs/FTO samples were sintered at 450, 550 and 630?C, in ambient air. The thermal treatment did not influence the crystal phase composition, preserving in all cases the anatase single phase. As expected, the crystalline anatase quality improved with the annealing temperature. Nevertheless, slight differences in nanotubular morphology, such as the appearance of grains inside the walls, were observed in the case of the sample sintered at 630?C. Chemical analysis by X-ray Photoelectron Spectroscopy of annealed samples revealed the presence of Sn inside TiO2 NTs, due to diffusion of Sn from the substrate to TiO2. For the substrate was used FTO glass whose top layer consists of SnO2 doped with F. Rutherford Backscattering Spectrometry and Time-of-Flight Elastic Recoil Detection Analysis were carried out to study the elemental depth profile of the films. It was found that the temperature of sintering controls the Sn diffusion inside TiO2 film. Sn atoms diffuse towards the TiO2 NTs surface for the samples annealed at 450 and 550?C. The diffusion is however hindered in the case of the heat treatment at 630?C. Besides, the Ti diffusion into the SnO2 underlayer was observed, together with the formation of TiO2/SnO2 interfaces. One then expected but not a great difference in absorption between samples, since all contained anatase phase, as confirmed by Diffuse Reflectance Spectroscopy. A higher amount of Sn was however detected for the sample annealed at 550?C, which accounts for a slight red absorption shift. The importance of controlling the annealing parameters of the anodized TiO2/FTO structures was highlighted through the formation of TiO2-SnO2 interfaces and the Sn insertion from FTO, which can play an essential role in increasing the photoperformances of TiO2 NTs/FTO based structures of photovoltaic cells.

Silicon plates were installed above the inner and outer divertor of the JET with the ITER-like wall (ILW) after the second and third ILW campaigns to monitor dust generation and deposition with the aim to determine the morphology and content of individual particles and co-deposits, including deuterium content. Particular interest was in metal-based particles: Be, W, steel, Cu. Ex-situ examination after two ILW campaigns was performed by a set of microscopy and ion beam methods including micro-beam nuclear reaction analysis and particle-induced X-ray emission. Different categories of Be-rich particles were found: co-deposits peeled-off from plasma-facing components (PFC), complex multi-element spherical objects, and solid metal splashes and regular spherical droplets. The fuel content on the two latter categories was at the level of 1 × 1016 at/cm−2 indicating that Be melting and splashing occurred in the very last phase of the second experimental campaign. The splashes adhere firmly to the substrate thus not posing risk of Be dust mobilisation. No tungsten droplets were detected. The only W-containing particles were fragments of tungsten coatings from the divertor tiles.

The cross sections of the 72Ge( α , γ)76Se and 1°7Ag(ρ, γ)1°8Cd reactions were measured at energies relevant to p-process nucleosynthesis. The new data, together with cross section results from our previous ( α , γ) measure-ments on 65Cu and 118Sn and other ( α , γ) cross-section data reported in lit-erature are compared with statistical model calculations performed using the latest version (1.9) of the statistical model code TALYS. In addition, the effect on these calculations of different combinations of the optical model potentials (OMPs), nuclear level densities (NLDs) and γ-ray strength functions (γSFs) entering the calculations was investigated.

The paper reports the study of an asymmetric detector with graphite contacts, about 20 µ m in diameter, buried within a synthetic single crystal diamond. To induce diamond-to-graphite transformation a femtosecond IR laser is used on the surface and bulk volume. Optical microscopy with crossed polarizers has evidenced optical anisotropy laterally the buried pillared contacts whereas the regions between pillars exhibited the presence of both tensile and compressive stress there around, as revealed with Raman spectroscopy mapping. Notwithstanding the strain, the buried electrodes showed linear electrical response and demonstrated ability to collect the charge carriers produced by 3.0 and 4.5 MeV protons as well as MeV electrons emitted by 90Sr. The charge collection efficiency (CCE) dependence on voltage evaluated using 4.5 MeV protons in the ±100 V range saturates at around 92±2% at 100 V, while coincidence experiments with MeV electrons confirmed that the whole pillars length is active in collecting the charge carriers. The mapping of CCE spatial distribution with an ion beam induced current technique showed that only a narrow (a few microns) damaged zone around the graphite electrodes has a reduced CCE, while the main diamond volume preserves excellent detection properties.

The interaction of the calcite surface with Co2+-rich aqueous solutions ([Co2+aq]initial = 1000 ppm, i.e., ca. 17 mM) was investigated by means of macroscopic experiments and surface spectroscopic techniques. In the case of the macroscopic experiments, calcite powder and monocrystals were immersed into solutions for different time periods (from 1 min to one month). The Ca concentrations in the filtrates was measured by means of atomic absorption spectrometry (AAS) while the interacted solids were studied using a combination of X-ray photoelectron spectroscopy (XPS) and 12C-rutherford backscattering spectrometry (12C-RBS). The macroscopic data showed a characteristic surface dissolution process, in parallel to the surface sorption processes. Adsorption and co-precipitation were seen for almost the entire immersion period for both calcite powder and monocrystals. The surface study by XPS (analyzed at a depth of approximately 12 nm) suggested that adsorption takes place in the first hour of the interaction, followed by incorporation of Co2+ into calcite surface layers, leading to the formation of a Co2+-bearing surface (co)precipitate, which occurs over a period of hours and days. The 12C-RBS measurements on calcite { 10 1 ¯ 4 } indicated that the thickness of this surface co-precipitate was 270 nm after one day and then stabilized at 320 nm after more than a week.

Samples extracted from several divertor tiles following the 2011-2012 operation of JET with the ITER-Like wall were analyzed using ion beam analysis methods, x-ray fluorescence spectroscopy, scanni ...