The compound LaNiO3 (LNO) is an interesting material due to its promising applications as bottom electrodes in several devices. Recently, the development of epitaxial thin films of this compound led to the discovery of transport property not well understood yet. In addition, it was recently reported that modification on LNO stoichiometry, as LaNi1,1O3, showed a significantly decrease in resistivity. In this work, the technique of Pulsed Laser Deposition (PLD) is used to obtain ultrathin films with accuracy and control of deposited thickness and to ensure an epitaxial growth of LNO on certain substrates. The interaction of a femtosecond laser beam with these thin films is discussed. The interaction of femtosecond laser beam with materials allows the formation of metallic nanoparticles from their previous structure, hence altering their stoichiometry, what is ideal for applications as the bottom electrode devices. Therefore, a detailed study of this system (LNO) and (LNO/BaTiO3) thin films deposited by PLD technique and irradiated by a femtosecond laser beam is of paramount importance and relevance to a better understanding of their physical and chemical properties for future applications in construction of ferroelectric and resistive RAM memories. This work has the proposal of studying systematically the effects generated by irradiation of a femtosecond laser beam in thin films of LaNiO3 and LaNiO3/BaTiO3 deposited epitaxially on different substrates by powerful technique known as PLD. The main objective is to understand the nucleation and growth of metallic nanoparticles on LNO films surface, also understanding the changes in LNO stoichiometry. It is expected that such modifications result in a decrease in the electrical resistivity values of this conducting layer, as well as an increase in the dielectric properties of the BaTiO3 layer. Characterizations techniques, such as XRD, SEM, AFM, XPS, TEM and electrical resistivity measurements at low temperatures, may provide a better understanding of the physical and chemical properties of this strongly correlated system.
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