Surface damage appears on materials irradiated by highly charged ions (HCI). Since a direct link has been found between surface damage created by HCI with the one created by swift heavy ions (SHI), the inelastic thermal spike model (i-TS model) developed to explain track creation resulting from the electron excitation induced by SHI can also be applied to describe the response of materials under HCI which transfers its potential energy to electrons of the target. An experimental description of the appearance of the hillock-like nanoscale protrusions induced by SHI at the surface of CaF ₂ is presented in comparison with track formation in bulk which shows that the only parameter on which we can be confident is the electronic energy loss threshold. Track size and electronic energy loss threshold resulting from SHI irradiation of CaF ₂ is described by the i-TS model in a 2D geometry. Based on this description the i-TS model is extended to three dimensions to describe the potential threshold of appearance of protrusions by HCI in CaF ₂ and to other crystalline materials (LiF, crystalline SiO ₂ , mica, LiNbO ₃ , SrTiO ₃ , ZnO, TiO ₂ , HOPG). The strength of the electron–phonon coupling and the depth in which the potential energy is deposited near the surface combined with the energy necessary to melt the material defines the classification of the material sensitivity. As done for SHI, the band gap of the material may play an important role in the determination of the depth in which the potential energy is deposited. Moreover larger is the initial potential energy and larger is the depth in which it is deposited.

Hardware-in-the-loop (HIL) simulation is an industrial practice that consists in testing a physical electronic control unit (ECU) against a real-time simulated model of a plant. Typical PWM applications run in the kHz range and can hardly be simulated using standard methods with the typical CPU time-steps that are at best in the 5-10 microseconds range. Migrating the computational load from a CPU to a Field Programmable Gate Array (FPGA) allows overcoming the limitation and achieving time-steps in the sub-microsecond range. Our work investigates the feasibility of hardware calculation engines intended for the FPGA-based HIL simulation using commercial floating-point cores, and using parallel multi-cycle multiply-accumulators (MACs). The effectiveness of the proposed multi-cycle accumulation scheme is here confirmed by considering a real-world application case study, that is a model of a permanent magnet synchronous motor (PMSM) driven by a three-phase two-level Insulated-Gate Bipolar Transistor (IGBT) inverter. Time-steps of 80 ns for the PMSM and 240 ns for the two-level inverter are reported. Simulation results are validated using the SimPowerSystems Matlab library with a 20 kHz PWM.

This paper presents the development of high fidelity real-time model of a permanent magnet synchronous motor (PMSM) drive, to be used in hardware-in-the-loop (HIL) application. The PMSM model is based on a finite-element analysis (FEA) method and implemented on an FPGA chip. The motor inductances and flux maps are computed from the JMAG-RT finite element analysis software. A 3-phase IGBT inverter drives the PMSM machine. Both models are designed in Simulink using the Xilinx Blockset and then automatically compiled and loaded on the FPGA using the RT-LAB real-time simulation platform. The complete PMSM drive model runs with an equivalent 10 nanosecond time step and has a latency of 300 ns (PMSM machine and inverter), with a total HIL delay from external PWM inputs to analog outputs with 1 microsecond settling time on the FPGA of just 1.3 microseconds.

Microstructural, electrical, and optical properties of undoped and Nd3+-doped SiOx/SiNy multilayers fabricated by reactive radio frequency magnetron co-sputtering have been investigated with regard to thermal treatment. This letter demonstrates the advantages of using SiNy as the alternating sublayer instead of SiO2. A high density of silicon nanoclusters of the order 1019 nc/cm3 is achieved in the SiOx sublayers. Enhanced conductivity, emission, and absorption are attained at low thermal budget, which are promising for photovoltaic applications. Furthermore, the enhancement of Nd3+ emission in these multilayers in comparison with the SiOx/SiO2 counterparts offers promising future photonic applications.

Silicon carbide has been considered a material for use in the construction of advanced high-temperature nuclear reactors. However, one of the most important design issues for future reactors is the development of structural defects in SiC under a strong irradiation field at high temperatures. To understand how high temperatures affect radiation damage, SiC single crystals were irradiated at room temperature and after being heated to 800 °C with carbon and silicon ions of energies ranging between 0.5 and 21 MeV. The number of displaced atoms and the disorder parameters have been estimated by using the channeling Rutherford backscattering spectrometry. The experimentally determined depth profiles of induced defects at room temperature agree very well with theoretical calculations assuming its proportionality to the electronic and nuclear-stopping power values. On the other hand, a significant reduction in the number of crystal defects was observed for irradiations performed at high temperatures or for samples annealed after irradiation. Additionally, indications of saturation of the crystal defect concentration were observed for higher fluences and the irradiation of previously defected samples.

In this article, we have fabricated and studied a new multilayer structure Si-SiO₂/SiN _x by reactive magnetron sputtering. The comparison between SiO₂ and SiN _x host matrices in the optical properties of the multilayers is detailed. Structural analysis was made on the multilayer structures using Fourier transform infrared spectroscopy. The effect of specific annealing treatments on the optical properties is studied and we report a higher visible luminescence with a control over the thermal budget when SiO₂ is replaced by the SiN _x matrix. The latter seems to be a potential candidate to replace the most sought SiO₂ host matrix.