Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.
DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.
The electromechanical coupling in ferroelectric materials is controlled by several coexisting structural phenomena which can include piezoelectric lattice strain, 180 degrees and non-180 degrees domain wall motion, and interphase boundary motion. The struc ...
The main mechanism of properties enhancement in the morphotropic phase boundary region separating tetragonal and rhombohedral phases of Pb(Zr1-xTix)O-3 (PZT) is related to polarization rotation. It is shown here that in proximity of the morphotropic phase ...
In this study, ceramic samples of lead zirconate titanate Pb(Zr0.42Ti0.58)O3 (PZT 42/58) doped with Fe (hard) and Nb (soft) were studied by Raman, infrared (IR) and THz spectroscopy in the temperature range from 900 to 20 K. From the evaluation of the IR a ...
The correlation between structure and electrical properties of lead-free (1-x)(Bi1/2Na1/2)TiO3-xBaTiO(3) (BNT-100xBT) polycrystalline piezoceramics was investigated systematically by in situ synchrotron diffraction technique, combined with electrical prope ...
Large bipolar strain of up to 0.36% (peak-to-peak value) was measured in BiFeO3 ceramics at low frequency (0.1 Hz) and large amplitude (140 kV/cm) of the driving field. This strain is comparable to that achievable in highly efficient morphotropic phase bou ...
The position of (Fe-Zr',(Ti)-V-O(center dot center dot))(center dot) defect complexes in Pb[Zr0.52Ti0.48]O-3 (PZT) piezoelectric ceramics was investigated by means of electron paramagnetic resonance (EPR) spectroscopy. The method of analysis pursued to obt ...
The depolarization temperature T-d of piezoelectric materials is an important figure of merit for their application at elevated temperatures. Until now, there are several methods proposed in the literature to determine the depolarization temperature of pie ...
It was noticed long time ago that the dielectric permittivity of BaTiO3 single crystals in the rhombohedral phase varies from observation to observation, but the microstructure mechanism behind this phenomenon remained unclear. We show that the variations ...
The dielectric response of hard (Fe-doped) and soft (Nb-doped) rhombohedral Pb(Zr0.58Ti0.42)1−xMexO3 (Me=Fe or Nb) ceramics was studied at subswitching conditions over a wide range of temperatures (50– 450 °C) and frequencies (10 mHz to 10 kHz). The result ...
The dielectric, electrical and structural properties of (1-x) (0.94Bi(1/2)Na(1/2)TiO(3)-0.06BaTiO(3))-xK(0.5)Na(0.5)NbO(3) (BNT-BT-xKNN) with x=0.09, 0.12, 0.15, and 0.18 were investigated as potential candidates for high-temperature capacitors with a work ...