El camp central dels treballs del grup és l'estudi i la caracterització de materials per a la seva aplicació en dispositius i/o circuits. Els materials estudiats són ceràmiques i compòsits piezoelèctrics, per a les seves aplicacions en microelectrònica i optoelectrònica. L‘atenció preferent se centra en l'anàlisi i la caracterització del comportament no lineal de materials, dispositius i circuits, i en l’estudi de la relació entre les condicions d'obtenció, el desordre estructural i les propietats de transport electrònic en polímers i materials orgànics conductors. L'estudi no lineal és necessari en les aplicacions en dispositius ultrasònics que utilitzen transductors ressonants. La caracterització no lineal de convertidors electrònics commutats DC-DC sotmesos tant a controls clàssics com moderns (diagrames de bifurcacions, dinàmiques quasiperiòdiques i caòtiques...) està orientada al disseny.

Pàgina web del grup de recerca

Recent Submissions

  • Microstructure effects on BaTiO3/BaTi0.8Zr0.2O3 composites properties 

    Martins Amaral, Thiago; Antonelli, Eduardo; Ochoa Guerrero, Diego A.; García García, José Eduardo; Hernandes, Antonio Carlos (2016-05-15)
    Article
    Restricted access - publisher's policy
    The dielectric, pyroelectric and ferroelectric properties of bilayered BaTiO3/BaTi0.8Zr0.2O3 ceramics are described and correlated with their microstructure. Different sintering times are employed to change the microstructure ...
  • Extrinsic response enhancement at the polymorphic phase boundary in piezoelectric materials 

    Ochoa Guerrero, Diego A.; Esteves, Giovanni; Jones, Jacob L.; Rubio-Marcos, Fernando; Fernández Lozano, José Francisco; García García, José Eduardo (2016-04-04)
    Article
    Open Access
    Polymorphic phase boundaries (PPBs) in piezoelectric materials have attracted significant interest in recent years, in particular because of the unique properties that can be found in their vicinity. However, to fully ...
  • Extensive domain wall contribution to strain in a (K,Na)NbO3-based lead-free piezoceramics quantified from high energy X-ray diffraction 

    Ochoa Guerrero, Diego A.; Esteves, Giovanni; Iamsasri, Thanakorn; Rubio-Marcos, Fernando; Fernández Lozano, José Francisco; García García, José Eduardo; Jones, Jacob L. (Elsevier, 2016-08)
    Article
    Restricted access - publisher's policy
    The origins of high piezoelectric properties in the lead-free (K,Na)NbO3-based tetragonal composition (K0.44Na0.52Li0.04)(Nb0.86Ta0.10Sb0.04)O3 (KNL-NTS) is investigated by quantifying the intrinsic and extrinsic contributions ...
  • Preisach modeling of temperature-dependent ferroelectric response of piezoceramics at sub-switching regime 

    Ochoa Guerrero, Diego A.; García García, José Eduardo (2016-04)
    Article
    Restricted access - publisher's policy
    The Preisach model is a classical method for describing nonlinear behavior in hysteretic systems. According to this model, a hysteretic system contains a collection of simple bistable units which are characterized by an ...
  • Efeito do dopante Ba sobre as propriedades estruturais e microestruturais de ceramicas Bi0.5Na0.5TiO3 

    Santos, Valdeci Bosco dos; Cerdeiras Montero, Elena; Mestres Vila, Lourdes; Machado, Rodrigo; Ochoa Guerrero, Diego A.; García García, José Eduardo (2015)
    Conference report
    Restricted access - publisher's policy
    Recently, Bi0,5Na0,5TiO3 (BNT) based ceramics has been widely studied as one promising material lead-free for piezoelectric applications. The Ba addition in BNT ((Bi0,5Na0,5)1-xBaxTiO3 - BNT-xBT) has attracted considerable ...
  • Nonlinear analysis of interconnected power converters: a case study 

    Benadero García-Morato, Luis; Cristiano, Rony; Pagano, Daniel J.; Ponce, Enrique (2015-09-01)
    Article
    Open Access
    In this paper the nonlinear dynamics of interconnected power converters in an islanded direct current (DC) microgrid is analyzed. By using a simplified scheme based on two cascaded converters we analyze the dynamical ...
  • Extrinsic contribution and instability properties in lead-based and lead-free piezoceramics 

    García García, José Eduardo (2015-11-01)
    Article
    Open Access
    Piezoceramic materials generally exhibit a notable instability of their functional properties when they work under real external conditions. This undesirable effect, known as nonlinear behavior, is mostly associated with ...
  • Stable p-doping in graphene and Terahertz spectroscopy 

    Ferrer Anglada, Núria; Gabriel Cortés, Daniel; Iqbal, M. Zahir; Eom, J. (2014)
    Conference report
    Open Access
  • THz-conductivity of CVD graphene on different substrates 

    Gabriel Cortés, Daniel; Sempere, Bernat; Colominas, Carles; Ferrer Anglada, Núria (Wiley-VCH, 2015-10-23)
    Article
    Restricted access - publisher's policy
    Optoelectronic properties of CVD graphene are charac-terized over a wide frequency range: THz, IR, visible and near-UV. We used Raman spectroscopy to characterize the synthesized graphene films. All graphene layers were ...
  • Growth and physical properties of highly oriented La-doped (K,Na)NbO3 ferroelectric thin films 

    Vendrell Villafruella, Xavier; Raymond, Oscar; Ochoa Guerrero, Diego A.; García García, José Eduardo; Mestres, Lourdes (2015-02-27)
    Article
    Restricted access - publisher's policy
    Lead-free (K,Na)NbO3 (KNN) and La doped (K,Na)NbO3 (KNN-La) thin films are grown on SrTiO3 substrates using the chemical solution deposition method. The effect of adding different amounts of Na and K excess (0-20 mol%) is ...

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