Gaspare Varvaro

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Magnetic interactions in silica coated spherical nanoporous assemblies of CoFe(2)O(4) nanoparticles have been investigated by low temperature field dependent remanent magnetization (M(DCD) and M(IRM)) and magnetization relaxation measurements. The synthesis procedure leads to the formation of spherical aggregates of about 50-60 nm in diameter composed of(More)
AIMS The aim of this work was to deposit silicon-substituted hydroxyapatite (Si-HAp) coatings on titanium for biomedical applications, since it is known that Si-HAp is able to promote osteoblastic cells activity, resulting in the enhanced bone ingrowth. MATERIALS AND METHODS Pulsed laser deposition (PLD) method was used for coatings preparation. For(More)
Impressive changes in the transport and ferromagnetic properties of Co-doped ZnO thin films have been obtained by postgrowth hydrogen irradiation at temperatures of 400 °C. Hydrogen incorporation increases the saturation magnetization by one order of magnitude (up to ∼1.50 μB/Co) and increases the carrier density and mobility by about a factor of two. In(More)
Magnetic nanoparticles (MNPs) are widely investigated due to their potential use in various applications, ranging from electronics to biomedical devices. The magnetic properties of MNPs are strongly dependent on their size and shape (i.e., morphology), thus appropriate tools to investigate their morphology are fundamental to understand the physics of these(More)
Two kinds of nanocomposites of transition metal oxides were synthesized and investigated. Each nanocomposite comprises nanoparticles of La0.67Ca0.33MnO3 and CoFe2O4 in similar volume fractions, however arranged with different morphologies. The temperature-dependent magnetic and electrical properties of the two systems are found to greatly differ, suggesting(More)
We report on the effect of microstructure and geometrically induced modifications of the magnetic properties of granular CoCrPt:SiO2 films with weakly interacting magnetic grains deposited on pre-structured GaSb nanocone templates fabricated by an ion erosion technique. By tuning the irradiation conditions, nanocone patterns of different cone sizes were(More)
A Fe-Co-Nb thin film materials library was deposited by combinatorial magnetron sputtering and investigated by high-throughput methods to identify new noncubic ferromagnetic phases, indicating that combinatorial experimentation is an efficient method to discover new ferromagnetic phases adequate for permanent magnet applications. Structural analysis(More)
The effect of the deposition temperature (Tdep) on the crystallographic orientation of pulsed laser-deposited FeCo/MgO(100) thin film was determined by means of X-ray reflectivity and high resolution trasmission electron microscopy analysis and was correlated with the magnetic anisotropy properties measured by angle dependent hysteresis loops. Highly(More)
A combined ultrahigh vacuum scanning tunneling microscopy (STM-UHV) and energy dispersive X-ray diffractometry/reflectometry (EDXD/EDXR) study of the evolution of face-centered cubic (fcc) Pt layer growth on MgO(100) by pulsed laser deposition as a function of the process parameters such as deposition temperature and deposition duration has been carried(More)
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