An objective analysis is carried out of the matricial models representing the polarimetric properties of light and material media leading to the identification and definition of their corresponding physical quantities, using the concept of the coherency matrix. For light, cases of homogeneous and inhomogeneous wavefront are analyzed, and a model for 3D polarimetric purity is constructed. For linear passive material media, a general model is developed on the basis that any physically realizable linear transformation of Stokes vectors is equivalent to an ensemble average of passive, deterministic nondepolarizing transformations. Through this framework, the relevant physical quantities, including indices of polarimetric purity, are identified and decoupled. Some decompositions of the whole system into a set of well-defined components are considered, as well as techniques for isolating the unknown components by means of new procedures for subtracting coherency matrices. These results and methods constitute a powerful tool for analyzing and exploiting experimental and industrial polarimetry. Some particular application examples are indicated.

When a thin film is deposited by physical vapour deposition, with the vapour flux arriving at an oblique angle from the substrate normal, and under conditions of sufficiently limited adatom mobility to create a columnar microstructure, the resulting structure is somewhat porous and grows at an angle inclined toward the vapour source. This technique called glancing angle deposition was used in this work to grow nanocrystalline cuprous oxide thin films by annealing in air of copper films deposited firstly by this method onto glass substrates. The films were characterized for their structural, surface morphological, compositional; electrical and optical properties by using X-ray diffraction (XRD), scanning electron microscopy (SEM), electrical resistivity and optical (transmittance and reflectance) measurement techniques. It was found that the above properties were strongly dependent on the obliquely angle deposition. The nanocrystallite size in these films was varied by varying the obliquely angle deposition. Optical studies show a direct allowed transition around in the range 1.5–1.85 eV for the annealed films. An enhancement in the oxidation process was observed for high obliquely angles deposition.

Silver films have been grown by electrodeposition technique on sprayed ITO coated substrates under different conditions. The transmittance in the visible range have been enhanced by adding silver and the sheet resistance was reduced for films prepared under -0.4 V applied voltage during 200 s. The attachment of Ag particles onto ITO surfaces was strong enough for further use such as in opto-electronic devices and solar cells.

Based on the first-principles simulations, the oxygen vacancies in the ultrathin HfO2 layer as the gate dielectric in a metal-oxide-semiconductor structure is found to result in the conductionband offset alignment around the vacancy. Thus an increase in the gate leakage current tunneling current comes when the oxygen vacancies appear in the HfO2 layer wherever the oxygen vacancies locate. The relative increase in the tunneling current caused by the oxygen vacancies slightly change with the increasing oxide thickness for a low oxide electric field.

Copper-doped SrBi2Nb2O9 (SBN) thin films have been fabricated on fused quartz substrates at room temperature by RF magnetron sputtering technique. The chemical composition and Cu concentration in the deposited films were characterized by X-ray fluorescence spectrometer. XRD analysis indicated that the films have a single phase of layered perovskite structure and Cu doping in SBN films did not degrade their crystallinity at the dopant concentration of 9.5%. The nonlinear optical properties of the samples were determined using a single beam z-scan technique at a laser wavelength of 532 nm with laser duration of 25 ps. The results showed that the value of $\chi ^{(3)}$ of Cu-doped SBN films is about twice larger than that of the undoped, which is comparable with that of some representative nonlinear optical materials, indicating that metal-doping in dielectric is effective to enhance their nonlinear optical properties. This suggests that Cu-doped SBN films have great potential in designing nonlinear optical devices.

We report here on the elaboration and transport properties of assemblies of ZnO nanoparticles and nanorods synthesized by organometallic chemistry. Two different methods have been used to prepare the samples. The first one consists in the deposition of the nano-objects on the substrate (drop-casting method) whereas the second one consists in the direct synthesis of the nano-objects on the substrate (in situ method). All the samples were highly resistive in the dark. Conductivity of as-grown nanorods was light-sensitive whereas the one of as-grown nanoparticles was not. Annealing the nanoparticles at 200 °C increases their dark resistance and strongly decreases their resistance under light. We analyse the transient photoconductivity when the light is abruptly switched on and off. The increase of the current when the light is switched on is fast and follows a simple exponential function. Decrease of the current when the light is switched off is slower and can be described by a stretched exponential function for short times and by a power law at longer times. Our various experiments are discussed in the light of other experiments on ZnO nanorods and CdSe nanoparticles, and to available models describing transport in assemblies of semiconductor nanoparticles.

OH- absorption bands of lithium tantalate crystals have been measured at room temperature, and the bands shape depending on the crystal composition has been observed. OH- absorption bands are fitted with three Lorentzian peaks by varying position, halfwidth, and area. Nearly constant peak positions (3461, 3475 and 3486 cm-1) for all samples are obtained. Hydrogenation is also performed to the crystals and its influence on the decomposed peaks (position, halfwidth and area) is investigated. The results show the fitting parameters of peaks have different values for crystals with different hydrogen concentration, which is interpreted by the different sites occupied by H+ in terms of the modified model about the location of Li-vacancy in the lattice. Additionally, it is shown that the halfwidth of peak at 3461 cm-1 remain unchanged regardless of hydrogen concentration, which make this parameter more suitable than other ones to determine the composition of LiTaO3 crystals. The quantitative relationship between the halfwidth of peak at 3461 cm-1 and the crystal composition is also presented.

The bulk lifetime $\tau _{n}$ and diffusion length L n of minority carriers vary through the height of a cast multicrystalline silicon (mc-Si) block. This variation is due to the segregation of metallic impurities during the directional solidification and the native impurity concentrations increase from the bottom to the top of the ingot, which is solidified last, while the ingot bottom, which is solidified first, is contaminated by the contact with the crucible floor. It is of interest to verify if a correlation exists between the bulk lifetime $\tau $ of as cut wafers and the conversion efficiency $\eta $ of solar cells. In a very large ingot (>310 kg), it was found that $\tau_{0}$ , in raw wafers, $\tau_{dif}$ in phosphorus diffused ones and L n in diffused wafers are smaller in the top and in the bottom of the ingot. The same evolution is observed in solar cells, however the diffusion length values L cel in the central part of the ingot are markedly higher than those found in diffused wafers, due to the in-diffusion of hydrogen from the SiN-H antireflection coating layer. The variations of $\eta $ and those of $\tau _{0}$ , along the ingot height, are well correlated, suggesting that the evaluation of $\tau _{0}$ can predict the properties of the devices. In addition, segregation phenomena around the grain boundaries are observed at the bottom of the ingots, due to a marked contamination by the crucible floor, and at its top where impurities are accumulated. These phenomena are linked to the long duration of the solidification process and the large amount of imperfect silicon used to cast the ingot.

In a normal and an abnormal ELCAD plasmas the density of electrons and positive ions were estimated from the earlier measured values of the cathodic current density, the cathode fall, the electric field, the length of cathode dark space, the kinetic energy, the last free path of positive ions hitting the cathode and the rate of secondary electron emission. In a normal ELCAD, the density of positive ions forming the space charge: $n_{sp}^{+}$ ≈ 5.7×1012 cm-3, the density of positive ions hitting the cathode: n + ≈ 1.1×1012 cm-3, the electron density at the cathode: $n_{e,c}$ ≈ 3.7×1011 cm-3, the electron density at the end of cathode dark space: n e ≈ 5.7×1012 cm-3 and the multiplication of electron in cathode dark space M ≈ 15.3 were obtained. In an abnormal case, $n_{sp}^{+}$ ≈ 2.1×1013 cm-3, n + ≈ 4.3×1012 cm-3, $ n_{e,c}$ ≈ 3.9×1012 cm-3, n e ≈ 2×1013 cm-3, M ≈ 5.17 were received.

An experimental study is presented involving the modelling of a concept which enables exterior dehydration of contaminating or fragile products. This concept is based upon the use of a ground-breaking film which is permeable exclusively to water vapour and semi-transparent to the sun's rays. The experimental results presented (derived from a campaign conducted with the help of a drying cell designed for this purpose) lead to the setting up of a simple model enabling the design and sizing of systems based on the use of this film to be considered.

The object of this work is to report a passive filter structure dedicated for power applications. The structure is based on a series combination of elementary notch filters resonating at harmonic frequencies of a base frequency (switching frequency of a converter). A calculation of values of the components used for a given performance is presented. In addition, energy study comparing the behavior of this new structure with that of a traditional LC filter shows that the same performances can be achieved with the 50% volume reduction.

We present the operating principle and a first experimental characterization of a holographic rangefinder, that couples a two wave mixing phase demodulation set-up with a frequency modulated laser source. In its first implementation, the system allows millimetre sensitivity on tens of meters measurement range with the ability to work with scattering surfaces.