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.
Using a density-functional approach, we study the dielectric permittivity across interfaces at the atomic scale. Focusing on the static and high-frequency permittivities of SiO2 films on silicon, for oxide thicknesses from 12 Angstrom down to the atomic sc ...
For the first time this paper presents strip lines fabricated using SU-8 as the dielectric material. It shows the complete fabrication process of micromachined strip lines with a total height of 35.5 um as well as their characterization by on-wafer S-param ...
We address the dielectric constant (or the polarizability for an isolated system) as obtained in density-functional supercell calculations with a discrete k-point sampling. We compare a scheme based on conventional perturbational theory to one based on a d ...
We introduce a variational total-energy functional to treat finite homogeneous electric fields with periodic boundary conditions and show that this functional can be implemented within a Car-Parrinello molecular dynamics scheme. The Coupling to an electric ...
Relaxor Pb(Sc-12/Ta-1/2)O-3 (PST) thin films have been prepared using mixed alkoxide and acetate precursors on TiO2/Pt/TiO2/SiO2/Si substrates. Relaxor behavior as evidenced by frequency dispersion of the permittivity as a function of temperature was obser ...
PbTiO3 thin films were prepared from alkoxide solution precursors and crystallized onto Pt/TiO2/SiO2/Si substrates. Microscopy observations revealed that the complexity of the domain walls structure decreased with the grain size. Dielectric, electrostricti ...
Pyrochlore free Pb(Mg1/3Nb2/3)O-3 (PMN) thin films were prepared from alkoxide-based solution precursors. The influence of different seeding layers and chemical solution on the microstructures is shown. Dielectric, electrostrictive, and piezoelectric prope ...
We treat homogeneous electric fields within density functional calculations with periodic boundary conditions. A nonlocal energy functional depending on the applied field is used within an ab initio molecular dynamics scheme. The reliability of the method ...
This thesis is devoted to the study of screening and polarisation effects in a quantum plasma of electrons and protons, when the system is close to a dilute gas of hydrogen atoms. This atomic phase is obtained by considering a coupled low-density and low-t ...
Relaxor Pb(Mg1/3Nb2/3)O3(PMN) and its solid solutions with ferroelectric PbTiO3 (PT) are of considerable interest from both the applications and the scientific point of view. In the past, many attempts were made to prepare and study the properties of these ...