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SmCo5 thin films with different thicknesses were prepared by electron beam evaporation on Kapton substrates. The out-of-plane hysteresis loops for different thicknesses reveal a maximum coercive field when the thickness is 15 nm. Using random magnetic anisotropy model, the thickness dependence of magnetic properties was studied in SmCo5 nanocrystalline films and several fundamental magnetic parameters were extracted. We have determined the local magnetic anisotropy constant K 1 which is found to increase with increasing film thickness except for t = 7 nm which is thought to arise from the structural imperfection of the SmCo5 films.

In this study, SmCo-based films with different thicknesses were grown on a Kapton substrate by ultra-high vacuum (UHV) evaporation process. Two effects on magnetic properties of SmCo films have been investigated: the effect of the variation of the magnetic layer thickness and the effect of the substrate temperature. The morphology and the structure were explored by atomic force microscopy and X-ray diffraction. It has been shown that the film morphology and its crystallographic orientation changed significantly with increasing thickness. Magnetic measurements reveal a strong correlation between magnetic and structural properties. The highest magnetic squareness ratio M r/ M s (0.8) and a maximum coercive field at room temperature, of about 2 kOe, are obtained when the SmCo layer thickness is 15 nm.

In the current study, we aim at simulating via a detailed Monte Carlo code, the electron penetration in a semi-infinite indium medium for incident energies ranging from 0.5 to 5 keV. Electron range, backscattering coefficients, mean penetration depths as well as stopping profiles are then reported. The results may be seen as the first predictions for low-energy electron penetration in indium target.

Based on a home-made Monte Carlo simulation, the electron backscattering coefficient, mean penetration depth, transmission probability, and transmission energy distribution of 1–5 keV electron normally incident penetrating in indium thin film targets have been computed. The trend of all features of interest as a function of the indium film thickness at both nanometric scale region and bulk material region has been examined and discussed. The present predictions may be seen as the first investigation regarding 1–5 keV electrons impinging on indium thin film targets. Copyright © 2016 John Wiley & Sons, Ltd.

Analytical expression of the target atomic number dependence of the numerical coefficient in the Nigam atomic screening factor is proposed here to approximate the Rutherford elastic scattering cross sections for slow electron beams impinging on selected solid targets (from Be to Au) in the primary energy range 1–4 keV. Applications are then proposed in terms of Monte Carlo calculation of backscattering coefficient. In this respect, tabulations of backscattering coefficients are here reported for slow electrons in solid targets of interest pointing out a reasonable agreement with the data available in the literature. Analytical expressions of the target atomic number dependence of the electron backscattering coefficient is also suggested for selected electron primary energies ranging from 1 to 4 keV allowing thus an accurate determination of backscattering coefficients for low-energy electrons in solid targets without any resort in Monte Carlo type calculations.

The aim of this work is to study the dielectric properties of thin films of tungsten trioxide. WO3 is an interesting material in the field of gas sensors. Here, we investigate the dependence of the electrical conductivity with temperature as well as the effect of the pressure on the thermal activation energy. For this purpose, we have used Impedance Spectroscopy (IS) to study the dielectric properties of RF sputtered WO3 thin films. Particularly, we have emphasized the effect of oxygen pressure on the surface conductivity.

The present study investigates the formulation and use of solid-shell finite element models which are able to model thin and thick, isotropic and multilayered composite structures using a purely 3D formulation based only on displacement dof. The second part of the paper deals with the optimization of composite structures, using a specific response surface method. This technique has been shown to be more efficient than classical gradient based methods. Several applications combining our solid-shell finite element model and the specific response surface method are shown in order to assess current procedure capabilities.