Title: Manipulating vortex dynamics in nanostructured YBCO films
Authors: A. Palau, V. Rouco, J. C. Gonzalez-Rosillo, R. Ortega, J. Suñé, Obradors X. and T. Puig
R. Ortega-Hernandez, M. Coll, J. C. Gonzalez-Rosillo, A. Palau, X. Obradors, E. Miranda, T. Puig and J. Suñé
Microelectronic Engineering, 147, 37-40 (2015)
DOI:10.1016/j.mee.2015.04.042
The resistive switching of CeO2−x/La0.8Sr0.2MnO3 bilayer structures has been studied. First, the resistive switching (RS) characteristics of La0.8Sr0.2MnO3 (LSMO) and the CeO2−x layers are studied separately. Then, the bilayer characteristics are analyzed. It has been demonstrated that inserting a thin CeO2−x layer between the LSMO film and the metal electrodes deeply modifies the resistive switching characteristics. The metal–insulator transition of the LSMO layer results from the oxygen diffusion in and out of the film. These effects are enhanced through the introduction of the CeO2−x layer due to the fact it acts as an oxygen reservoir.
Hola!
My name is Alex and I just started my PhD in Physics in
superconductivity. I love the idea to work in a field which might change
our future to a greener one (loss less power grids, fusion plants,
energy storages for green energy) and combines basic research with
applications. I graduated from Vienna University of Technology but
studied some semesters abroad in Göttingen, Germany and at the High
Magnetic Field Lab in Tallahassee, Florida. I enjoy deepening my
knowledge and understanding of physics and traveling and experiencing
new cultures at the same time and I’m looking forward to a fruitful and
great time with all of you here at the ICMAB!
A. Queraltó, A. Pérez del Pino, M. de la Mata, J. Arbiol, X. Obradors and T. Puig
Crystal Growth and Design 15, 1957-1967 (2015)
DOI: 10.1021/acs.cgd.5b00115
The epitaxial growth of Ce0.9Zr0.1O2–y (CZO) thin-films on yttria-stabilized zirconia (YSZ) (001) single crystal and YSZ (001)/stainless steel (YSZ/SS) technological substrates is investigated by pulsed laser irradiation of solution-derived cerium–zirconium precursor layers using a UV Nd:YAG laser source at atmospheric conditions. The influence of laser processing parameters on the morphological and structural properties of the obtained films is studied by atomic force and transmission electron microscopies, as well as X-ray diffractometry. The analyses performed demonstrate that laser treatments enable the epitaxial growth of tens of nanometers thick CZO films with a crystallization kinetic process several orders of magnitude faster than that of conventional thermal annealing. Fully epitaxial films are attained using stainless steel (SS) flexible tapes as a substrate. Even though photochemical mechanisms are not fully discarded, it is concluded that photothermal processes are the main contribution responsible for the fast epitaxial crystallization.
Hello, my name is Alvaro Calleja, I’m an Electronic Design Engineer and I have just joined today the group of Superconducting Materials and Nanostructure at Large Scale at ICMAB. My tasks are related to the development of electronic control and monitoring systems for the project of Development of a New Generation of Electric Generators with Superconducting Coils, within of Teresa Puig’s group and under the supervision of Dr. Xavier Granados. See you around at ICMAB!
P Roura, J. Farjas, H. Eloussifi, L. Carreras, S. Ricart, T. Puig Molina and X. Obradors
Thermochimica Acta 601, 1-8 (2015)
DOI:10.1016/j.tca.2014.12.016
The thermal decomposition of several metal organic precursors, used in the preparation of YBa2Cu3O7−xsuperconducting coated conductors (Cu acetate, Cu, Y and Ba trifluoroacetates and Ce propionate) is analyzed by means of several thermoanalytical techniques (TG/DTA, MS and DSC). In all cases, the metal organic precursors deposited as thin films decompose differently than powders from the same precursors. In thin films, decomposition is facilitated by the easier transport of reactive gas from the surrounding atmosphere and by the easier out-diffusion of volatile products. Consequently, films decompose at lower temperature and are more sensitive to the presence of any residual reactive gas in the furnace. Good thermal contact with the substrate is also shown to minimize overheating in films and avoid combustion processes that are otherwise often observed during the thermal decomposition of powders. Finally, the formation and stability of intermediate products towards the oxide formation, such as metal fluorides, differs in films because of the easier gas exchange. With respect to powders, these compounds are much less stable in films, where their decomposition temperature can be lowered by several hundreds of degrees Celsius. While in some cases the behaviour of films can be predicted by analyzing varying masses of precursor powders, this is not always the case. Therefore, thermal analysis carried out on films is recommended to avoid erroneous conclusions about materials preparation drawn from powders.
