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The ion energies and fluxes in the high power impulse magnetron sputtering plasma from a Nb target were analysed angularly resolved along the tangential direction of the racetrack. A reactive oxygen-containing atmosphere was used as such discharge conditions are typically employed for the synthesis of thin films. Asymmetries in the flux distribution of the recorded ions as well as their energies and charge states were noticed when varying the angle between mass-energy analyser and target surface. More positively charged ions with higher count rates in the medium energy range of their distributions were detected in +EB than in -EB direction, thus confirming the notion that ionisation zones (also known as spokes or plasma bunches) are associated with moving potential humps. The motion of the recorded negatively charged high-energy oxygen ions was unaffected. NbOxthin films at different angles and positions were synthesised and analysed as to their structure and properties in order to correlate the observed plasma properties to the film growth conditions. The chemical composition and the film thickness varied with changing deposition angle, where the latter, similar to the ion fluxes, was higher in +EB than in -EB direction.

The structure, morphology, composition, magnetism, and magneto-optical (MO) response of FePd films sputter deposited at different temperatures on a monocrystalline V(001) buffer layer is studied. It is observed that the perpendicular magnetic anisotropy (PMA) could be ascribed to the V interdiffusion and the formation of a FeV alloy, being the global sample saturation magnetization also reduced.

Epitaxial Nb thin films deposited onto the same crystalline insulating surface can evolve in very different fashions depending on specific deposition conditions, thereby affecting their microstructure, surface morphology and superconducting properties. Here, we examine and compare the microstructure and ensuing surface morphology from two distinct Nb/MgO series each with its own epitaxial registry-namely Nb(001)/MgO(001) and Nb(110)/MgO(001)-leading to distinct surface anisotropy and we closely examine the dynamical scaling of the surface features during growth. We compare our findings with those in other metal/MgO epitaxial systems and for the first time, general scaling formalism is applied to analyze anisotropic surfaces exhibiting biaxial symmetry. Further, Power Spectral Density is applied to the specific problem of thin film growth and surface evolution to qualify the set of deposition conditions leading to smoother surfaces. We find good correlation between the surface morphology and microstructure of the various Nb films with superconducting properties such as their residual resistance ratio and lower critical field. [ABSTRACT FROM AUTHOR]

We present our investigations on the enhancement of magneto-optical (MO) effects in nanocomposite Au–Co thin films. All the samples in this study were obtained by cosputter deposition varying the relative Au:Co composition and the growth temperature. A strong enhancement of the transverse MO activity is observed when surface plasmons are excited in the Kretschmann configuration. The correlation between the nanocomposite films' microstructure, morphology, composition, and their optical response under surface plasmon resonance excitation and their MO enhancement is discussed. [ABSTRACT FROM AUTHOR]

The morphological and magnetic properties of Co nanoparticles deposited by triode sputtering on Si3N4 at 550 °C are reported. The nominal thickness of Co ranges from 2 up to 15 nm, and two different capping layers, Au and Pt, are used. The nanoparticles were characterized by x-ray diffraction and atomic force microscopy. Morphological and structural studies show that the nanoparticles grow in a well-defined nanostructured pattern and adopt a hexagonal closed packed crystalline structure. Moreover, the average particle size and the particle size dispersion increase as the thickness increases, due to percolation. Experimental characterization of effective anisotropy field was carried out with transverse susceptibility. Transverse susceptibility measurements reveal an in-plane isotropic magnetic behavior. Both the effective anisotropy field and the coercive field increase as the particle size increases, following a D6 dependence, which is typical for three-dimensional structures in the framework of the random anisotropy model. The relationship between the particle size distribution and the anisotropy field distribution is shown, explaining the significant dependence of the magnetic behavior on the Co layer thickness. On the other hand, different capping layers give rise to a change in the magnetic response due to the modification of the interparticle interaction. [ABSTRACT FROM AUTHOR]

We present a study of the optical and magneto-optical (MO) properties of Co nanoparticles embedded in ZrO2 in the spectral range from 1.4 to 4.3 eV. The nanostructured films were prepared by pulsed laser deposition in a wide range of Co nanoparticle concentrations varying from 20% to 80%. For Co concentration lower than x∼0.45 the size of the nanoparticles was found to remain almost constant (D∼2.5 nm), whereas it increases above it. Differences are found between the optical and MO constant of the Co nanoparticles and those of continuous Co films. Those differences are associated with size effects of the intraband contribution inside the nanoparticles. [ABSTRACT FROM AUTHOR]

We present a study of the optical and magneto-optical (MO) properties of Co nanoparticles embedded in ZrO2 in the spectral range from 1.4 to 4.3 eV. The nanostructured films were prepared by pulsed laser deposition in a wide range of Co nanoparticle concentrations varying from 20% to 80%. For Co concentration lower than x∼0.45 the size of the nanoparticles was found to remain almost constant (D∼2.5 nm), whereas it increases above it. Differences are found between the optical and MO constant of the Co nanoparticles and those of continuous Co films. Those differences are associated with size effects of the intraband contribution inside the nanoparticles. [ABSTRACT FROM AUTHOR]

We present a structural, morphological, magnetic, and magneto-optical study of cobalt nanoparticles deposited on 50 Å AlN/c-sapphire substrates and embedded in an AlN matrix. The dependence of the properties of Co nanoclusters deposited on AlN with growth temperature and amount of deposited Co are studied and discussed. Also we directly compare the properties of as grown and AlN embedded Co nanoclusters and show that the AlN matrix has a strong impact on their magnetic and magneto-optical properties. [ABSTRACT FROM AUTHOR]