CEMAD - Caracterització elèctrica de materials i dispositius
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.
Enviaments recents
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Insights into the early size effects of lead-free piezoelectric Ba0.85Ca0.15Zr0.1Ti0.9O3
(John Wiley & sons, 2023-11-15)
Article
Accés obertBa0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) stands out among lead-free ferroelectric oxides under consideration to replace state-of-the-art high-sensitivity piezoelectric Pb(Zr,Ti)O3, for a range of energy conversion ceramic technologies. ... -
Particle size effect on the microstructure and the aging process of flash-sintered barium titanate from micro and nanopowders
(Royal Society of Chemistry (RSC), 2023-08-08)
Article
Accés obertFlash sintering is a novel sintering technique that allows high-density ceramics to be obtained at low temperatures and using short dwell times, thus providing an energy-efficient alternative to conventional sintering. The ... -
Fine-grained high-performance Ba0.85Ca0.15 Zr0.1Ti0.9O3 piezoceramics obtained by current-controlled flash sintering of nanopowders
(Elsevier, 2023-12)
Article
Accés obertDue to environmental concerns, extensive research has been carried out to develop high-performance lead-free piezoceramics capable of replacing commercial lead-based materials. The lead-free (Ba0.7Ca0.3)TiO3 -Ba(Zr0.2Ti0.8)O3 ... -
Features of the structural and dielectric properties in BaTi1-xSnxO3 ferroelectric ceramics
(2023-07-27)
Article
Accés restringit per política de l'editorialThe demand to produce clean energy has been increasing over the last years due to the various climate changes, which are strongly afflicting the world. Therefore, it is necessary to implement new and alternative energy ... -
In-depth analysis of smooth and nonsmooth bifurcations for an open-loop boost converter feeding constant power loads in discontinuous conduction mode
(2023-03-30)
Article
Accés restringit per política de l'editorialThis paper presents a study of the existence conditions of limit cycles and mechanisms when losing their stability in an open-loop DC–DC boost converter loaded with a constant power load and operating in discontinuous ... -
Light-induced strain and its correlation with the optical absorption at charged domain walls in polycrystalline ferroelectrics
(Elsevier, 2023-06)
Article
Accés obertPhotostrictive materials have a growing interest because of their great potential as light-driven actuators, among other optomechanical applications. In this context, the optical control of macroscopic strain in ferroelectrics ... -
Visible-light-control of dielectric permittivity in ferroelectrics with charged domain walls
(American Physical Society (APS), 2023-03-29)
Article
Accés restringit per política de l'editorialOptical control of functional properties in ferroic materials is now a highly appealing topic because it may entail different paradigms for future technologies. In ferroelectrics, in particular, controlling the properties ... -
Bifurcation phenomena in open-loop DCM-operated DC–DC switching converters feeding constant power loads
(2023-02-19)
Article
Accés obertConstant power loading is an effect that appears in multiple-stage energy conversion systems with individually regulated switching power converters. In a two-stage system, an upstream or source converter drives one or more ... -
Light-driven motion of charged domain walls in isolated ferroelectrics
(American Physical Society (APS), 2022-12-26)
Article
Accés obertLight-induced ferroelectric domain wall motion turns out to be a promising phenomenon to de- velop new photo-controlled devices. However, the physical origin of this ligh-matter coupling when material is irradiated with ... -
Tailoring the microstructure by a proper electric current control in flash sintering: The case of barium titanate
(Elsevier, 2022-10)
Article
Accés obertFlash sintering is arousing growing interest because high-density ceramics can be obtained at lower temperatures and shorter dwell times than conventional sintering. However, not only temperature and dwell times should be ... -
Unfolding kinetic fragility in relaxor ferroelectrics
(American Institute of Physics (AIP), 2021-10-07)
Article
Accés obertThe fragility parameter is one of the most important material constants that is extensively used in glass science, playing a central role in the enhancement of the understanding the glass formation process of disordered ... -
Effect of the incorporation of BiFeO3 on the structural, electrical and magnetic properties of the lead-free Bi0.5Na0.5TiO3
(2021-11-05)
Article
Accés obertPowders of the system (1–x)Bi0.5Na0.5TiO3–xBiFeO3 (x = 0, 0.02, 0.08, 0.10) are synthesized by the combustion reaction method. The crystal structure and the particle size of Bi0.5Na0.5TiO3 are modified by the incorporation ...