0000000000988813
AUTHOR
Eduardo Alves
Plasma-wall interaction studies within the EUROfusion consortium: Progress on plasma-facing components development and qualification
This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission.
Overview of the JET results in support to ITER
The 2014–2016 JET results are reviewed in the light of their significance for optimising the ITER research plan for the active and non-active operation. More than 60 h of plasma operation with ITER first wall materials successfully took place since its installation in 2011. New multi-machine scaling of the type I-ELM divertor energy flux density to ITER is supported by first principle modelling. ITER relevant disruption experiments and first principle modelling are reported with a set of three disruption mitigation valves mimicking the ITER setup. Insights of the L–H power threshold in Deuterium and Hydrogen are given, stressing the importance of the magnetic configurations and the recent m…
Luminescence and structural properties of defects in ion implanted ZnO
ZnO substrates and films were intentionally implanted with rare earth and transition metal ions. The influence of the implantation and subsequent air thermal annealing treatments on the structural and optical properties of ZnO samples were studied by using Rutherford backscattering spectrometry and low temperature photoluminescence techniques. Intraionic Tm-related emission was observed for bulk and ZnO films. Similarly, Eu and Tb-doped ZnO films follow the same trend observed in bulk samples. No intraionic related emission was observed for Eu-doped samples even being the ion in Zn sites and for the Tb-doped samples ion segregation was observed for thermal annealing temperatures above 800 °…
Optical active centres in ZnO samples
Abstract In recent years, there has been a resurgence in the interest in the use of ZnO (Eg ∼ 3.37 eV) as a material for a wide range of opto-emitter applications spanning visible and short wavelengths. Bulk, thin films and nanomaterials obtained using different synthesis methods have been investigated for optoelectronic and biotechnological device applications. Nominally undoped bulk samples typically present a myriad-structured near-band-edge recombination, mainly due to free/bound excitons and donor–acceptor pair transitions. Furthermore, deep level emission due to intrinsic defects and extrinsic impurities, such as transition metal ions, are commonly observed in different grades of bulk…
Selective area vapor-phase epitaxy and structural properties of Hg1 − xCdxTe on sapphire
Selective area (SA) Hg1 − xCdxTesapphire layers have been grown using the recently developed technique of the vapor-phase epitaxy (VPE) of Hg1 − xCdxTe layers on CdTesapphire heteroepitaxial substrates (HS), which we have called “VPE on HS technique” (Sochinskii et al., J. Crystal Growth 149 (1995) 35; 161 (1996) 195). First, planar CdTe (1 1 1) 5–7 μm thick layers were grown on sapphire (0 0 0 1) wafers by metalorganic vapor-phase epitaxy (MOVPE) at 340°C for 1–2.5 h using dimethylcadmium and di-isopropyltellurium as precursors. Second, CdTe/sapphire mesas were formed using standard photolithography in the form of alternating parallel linear arrays consisting of 500 × 70 μm2 elements. Thir…
Fuel inventory and material migration of JET main chamber plasma facing components compared over three operational periods
Fuel retention and material migration results from JET ITER-like wall beryllium limiter tiles are presented for three operating periods. Ion beam analysis results support the general picture of erosion during limiter configurations with local deposition on tile ends far into the scrape off layer. Similar trends of fuel concentrations are observed in all JET operating periods; (i) low on surfaces exposed to high heat flux and erosion and (ii) higher in deposits. The pattern of fuel retention and deposition correlates with heat flux and distribution of limiter plasmas touching inner and outer limiters. The D/Be ratio in the thickest deposit is similar to 0.01. Global fuel retention attributed…
The influence of Sb doping on the local structure and disorder in thermoelectric ZnO:Sb thin films
The experiment at HASYLAB/DESY was performed within the project I-20200161 EC. The research leading to this result has been supported by the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01–2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2. This work was carried out in part through the use of the INL Advanced Electron Microscopy, Imaging and Spectroscopy Facility. This work (proposal ID 2018–020-022469) was car…