Electronic Band Transitions in γ-Ge3N4
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 and 2019-2020 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. Support from Estonian Research Council grant PUT PRG 619 is gratefully acknowledged. The multi-anvil experiments at LMV were supported by the French Government Laboratory of Excellence initiative no ANR-10-LABX-0006, the Région Auvergne and the European Regional Development Fund (ClerVolc Contribution Number 478).
The polarimetric and helioseismic imager on solar orbiter
This paper describes the Polarimetric and Helioseismic Imager on the Solar Orbiter mission (SO/PHI), the first magnetograph and helioseismology instrument to observe the Sun from outside the Sun-Earth line. It is the key instrument meant to address the top-level science question: How does the solar dynamo work and drive connections between the Sun and the heliosphere? SO/PHI will also play an important role in answering the other top-level science questions of Solar Orbiter, as well as hosting the potential of a rich return in further science. SO/PHI measures the Zeeman effect and the Doppler shift in the FeI 617.3nm spectral line. To this end, the instrument carries out narrow-band imaging…
Defects induced by He+ irradiation in γ-Si3N4
International audience; Formation and evolution of defect levels in the electronic structure of silicon nitride with cubic spinel structure, -Si 3 N 4 , after the irradiation with He + ions was investigated using spectroscopic techniques. Strong changes of cathodoluminescence (CL), photoluminescence (PL), photoluminescence excitation (PLE) and Raman spectra were detected. In particular, excitonic PL was significantly inhibited and a new near-IR band appeared with the band gap excitation h≥E g =5.05 eV. This was explained by an effective trapping of photoinduced electrons and holes by charged defects. The spectral shift of PL with the excitation photon energy indicated heterogeneous nature…