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7 páginas, 8 figuras.-- et al., CdSe/ZnS core–shell quantum dots (QDs) have been immobilized by ultraviolet matrix-assisted pulsed laser evaporation (UV-MAPLE) onto SiO2 glass substrates covered by silica thin films. The silica thin films were deposited by the sol–gel method. An UV KrF* (λ = 248 nm, τfwhm 25 ns) excimer laser source was used for the laser immobilization experiments. Toluene was chosen as solvent material for the preparation of the composite MAPLE targets. The surface morphology and growth mode of the deposited structures were investigated by optical and atomic force microscopy in acoustic (dynamic) configuration. The crystalline structure and chemical composition of the base material used for the preparation of the MAPLE targets as well as the laser transferred QDs were studied by transmission electron microscopy and energy dispersive X-ray spectroscopy. The functional properties of the immobilized QDs were studied by fluorescence microscopy. The immobilized materials form self-organized 2D arrays constituted by complex CdSe/ZnS core–shell QDs preserving the functional properties of the base material used for the preparation of the MAPLE targets., The authors acknowledge the financial support from the Spanish National Research Council under the Contract Nos. 200860I211 and 200960I015, the Spanish Ministry of Science and Innovation for the PTA2008-1108-I contract, the Portugal- Spanish Bilateral Agreement No. 2007PT0007, and the Romanian National University Research Council under the Contract IDEAS No. 652.

The deposition of single phase Li3xLa2/3 - xTiO3 (LLTO) thin films remains very challenging. The growth of the perovskite phase is in competition with the insulating La2Ti2O7 phase when prepared at high oxygen pressure by PLD. Nevertheless, we have achieved epitaxial growth of LLTO on different (001) oriented substrates such as LaAlO3, SrTiO3 and MgO despite a large lattice mismatch of up to + 8.8%. We also determined the percentage of lithium excess in the target necessary to reach a maximum ionic conductivity. However, the presence of the blocking La2Ti2O7 phase strongly hinders the lithium ion migration and reduces the total conductivity compared to bulk properties., F.A. would like to thank the support of the Ministry of Industry of the Basque Country for their financial support through the Etortek program untitled Energigune´13.

Under the terms of the Creative Commons Attribution (CC BY) license to their work., We report on the magnetic and structural properties of ferromagnetic-insulating La2CoMnO6-δ thin films grown on top of (001) SrTiO3 substrates by means of RF sputtering technique. Careful structural analysis, by using synchrotron X-ray diffraction, allows identifying two different crystallographic orientations that are closely related to oxygen stoichiometry and to the features (coercive fields and remanence) of the hysteresis loops. Both Curie temperature and magnetic hysteresis turn out to be dependent on the oxygen stoichiometry. In situ annealing conditions allow tailoring the oxygen content of the films, therefore controlling their microstructure and magnetic properties., We acknowledge financial support from the Spanish MEC (MAT2011-29081 and MAT2012-33207), CONSOLIDER (CSD2007-00041), and FEDER program. R.G., L.L.-M. and N.B. thank the Spanish MINECO for the financial support through the FPI program. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under Grant Agreement No. 312284.

The present study is devoted to analyze the compatibility of yttria-stabilized zirconia thin films prepared by pulsed laser deposition and metalorganic chemical vapor deposition techniques, with microfabrication processes based on silicon technologies for micro solid oxide fuel cells applications. Deposition of yttria-stabilized zirconia on Si/SiO2/Si3N4 substrates was optimized for both techniques in order to obtain high density and homogeneity, as well as a good crystallinity for film thicknesses ranging from 60 to 240 nm. In addition, stabilized zirconia free-standing membranes were fabricated from the deposited films with surface areas between 50 x 50 microm2 and 820 x 820 microm2. Particular emphasis was made on the analysis of the effect of the nature of the deposition technique and the different design and fabrication parameters (membrane area, thickness and substrate deposition temperature) on the residual stress of the membranes in order to control their thermomechanical stability for application as electrolyte in micro solid oxide fuel cells.

10 páginas, 8 figuras.-- et al., The search for new strategies to enhance the oxide ionic conductivity in oxide materials is a very active field of research. These materials are needed for application in a new generation of more efficient and durable solid state electrochemical devices such as reduced-temperature Solid Oxide Fuel Cells (SOFC's). Recently published results have claimed that sputtered yttria stabilised zirconia (YSZ)/SrTiO3 (STO) heterostructures show enhanced oxygen ion conductivity, by about eight orders of magnitude, with respect to that expected for YSZ and STO bulk values. The YSZ/STO heterostructures obtained in this work from Pulsed Laser Deposited (PLD) films, also show enhanced conductivity of a similar order. However, the fact that our structures show different relative orientations indicates that the conductivity enhancement may not be associated to a particular crystallographic arrangement at the interface. The combined characterisation of the conductivity dependence on oxygen partial pressure and direct oxygen diffusion by means of tracer experiments clearly demonstrate that the enhancement observed is related to the electronic rather than ionic conductivity., The authors also acknowledge the financial support of Spanish Government through projects: MAT2008-04931 and Consolider-Ingenio 2010-CSD2008-023. Two of the authors (A.C. and M.B.) acknowledge the support of their postdoctoral fellowships from the Spanish Ministry of Science and Innovation. DWM acknowledges the support of the Royal Academy of Engineering.

The present study is devoted to analyze the compatibility of yttria-stabilized zirconia thin films prepared by pulsed laser deposition technique for developing new silicon-based micro devices for micro solid oxide fuel cells applications. Yttria-stabilized zirconia free-standing membranes with thicknesses from 60 to 240 nm and surface areas between 50x50 μm 2 and 820x820 μm 2 were fabricated on micromachined Si/Si0 2 /Si 3 N 4 substrates. Deposition process was optimized for deposition temperatures from 200°C to 800°C. A complete mechanical study comprising thermomechanical stability, residual stress of the membranes and annealing treatment as well as a preliminary electrical characterization of ionic conductivity was performed in order to evaluate the best processing parameters for the yttria-stabilized zirconia membranes.

Under the terms of the Creative Commons Attribution (CC BY) license to their work., A route to engineer the intrinsic colossal magnetoresistance (CMR) response in manganite thin films through an accurate control of the growth kinetics is presented. It is shown that under specific growth conditions, a particular strained state, substantially different from that of bulk-like materials and standard films, can be quenched up to film thicknesses around 60 nm. This strained state exhibits the same structural fingerprints of the interfacial dead layer in standard films and promotes surface morphology instabilities, which end up with the formation of self-organized nanopits array. At the same time, it has profound effects on the intrinsic magnetoelectronic properties of the films that exhibit an enhanced intrinsic CMR response., We acknowledge financial support from the Spanish MEC (MAT2011-29081 and MAT2012-33207), CONSOLIDER (CSD2007-00041), and FEDER program. Z.K. thanks the Spanish MINECO for the financial support through the RyC program. We thank Helmholtz-Zentrum Berlin for the allocation of neutron/synchrotron radiation beamtime. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under Grant Agreement No. 312284.

A systematic study of the growth process of LaMnO3 (LMO) thin films, by pulsed laser deposition, on top of SrTiO3 substrates under different oxygen partial pressures (PO2) is reported. It is found that the accommodation of the orthorhombic LMO phase onto the cubic STO structure, i.e. the amount of structural strain, is controlled by background oxygen pressure. We demonstrate that magnetic behaviour can be continuously tuned from robust ferromagnetic (FM) ordering to an antiferromagnet. These results strongly point to a strain-induced selective orbital occupancy as the origin of the observed FM behaviour, in agreement with recent theoretical calculations., We acknowledge financial support from the Spanish MINECO (MAT2011-29081 and MAT2012-33207), CONSOLIDER (CSD2007-00041), and FEDER program. We thank P. García for his kind assistance during x-ray experiments. ICN2 acknowledges support from the Severo Ochoa Program (MINECO, Grant - SEV 2013-0295). ZK thanks the support from the Ministry of Education, Science, and Technological Development of Republic of Serbia through Project III45018.