Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.
AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.
This paper discusses the mechanisms that can contribute to the enhanced longitudinal piezoelectric effect along nonpolar directions in perovskite crystals, such as BaTiO3, PbTiO3, KNbO3, Pb(Mg1/3Nb2/3)O-3-PbTiO3 and Pb(Zn1/2Nb2/3)O-3-PbTiO3. Piezoelectric ...
Hysteretic and nonlinear dielectric behaviour in ferroelectric ceramics has been of interest since 1950s, when these materials found application in various electronic devices. Presently, these phenomena concern with important areas of science, technology a ...
The thermal stability of amorphous ionic solids is usually attributed to kinetic considerations related to mass transport. However, there are a number of amorphous ionic solids, which have recently been described, whose unusual resistance to nucleation and ...
The present study reports on the preparation and structural characterization of dense NaNbO3 ceramics with ultrafine grain size. Nanocrystalline raw powders obtained via microemulsion mediated synthesis were consolidated to green compacts, sinterforged to ...
Strontium barium niobate (SrxBa1-xNb2O6, shortly SBN) is a solid solution system with tetragonal tungsten bronze crystal structure. It exhibits a ferroelectric phase with only one polar axis and a transition temperature depending on the Sr/Ba ratio. This t ...
The piezoelectric effect in ferroelectric single crystals and ceramics is investigated considering intrinsic (lattice), and extrinsic (originating mainly from displacement of domain walls) contributions. The focus of the study of intrinsic properties is on ...
The transverse piezoelectric coefficient (d(31)(star)) has been calculated for tetragonal barium titanate (BT) and lead titanate (PT) cut along nonpolar axes, over a range of temperatures, using the phenomenological Landau-Ginzburg-Devonshire theory. It is ...
Using density functional theory, we investigate the structural, vibrational, and dielectric properties of titanium oxides and silicates, which have attracted considerable attention in the framework of the quest for alternative high-K materials. For the oxi ...
We present a model for reverse domain nucleation in ferroelectrics, which takes into account ferroelectric-electrode coupling in both homogeneous and random cases. The model provides a solution to the coercivity paradox-i.e., the large discrepancy between ...
Structural and dielectric properties of epitaxial SrTiO3 (STO) thin films on LaAlO3 substrates fabricated by a two-step growth technique using pulsed laser deposition were investigated by in situ and ex situ observations in terms of strain relaxation from ...