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The postresonator method proposed by Hakki and Coleman for the measurement of dielectric properties of solids in the microwave region is reexamined. Based on the experiments performed around 10 GHz, the limitations of the method in loss determination for m ...
It was observed that the dielectric permittivity of PbMg1/3Nb2/3O3 (PMN) relaxer ceramics increases with increasing amplitude of the applied ac field. A strong nonlinearity occurs at temperatures where the frequency dispersion of the dielectric response is ...
A model of relaxors as superparaelectrics with a distribution of the local transition temperature has been investigated. The necessary model parameters are obtained from the analysis of the static polarization response of lead magnesium niobate and then em ...
The concepts of lifetime and relaxation semiconductors introduced by van Roosbroeck and Casey are reconsidered for amorphous semiconductors and the effect of localized states on the lifetime/relaxation criterion specified: The quantity to be considered is ...
In the present study, piezoelectric, conductivity and dielectric measurements have been performed on virgin and fatigued ferroelectric PZT thin films prepared by spin-on sol-gel deposition process on Si/SiO2/Ti/Pt substrates. By fatiguing, the polarisation ...
Pb(Zr0.70Ti0.30)O-3 rhombohedral thin films of (100), (110)/(111) and (111) textures were prepared on Si wafers with Ti/Pt electrodes. Microstructures and textures were characterized by XRD, SEM, TEM, and AFM. Ferroelectric, dielectric and fatigue properti ...
Unlike Pb(Mg1/3Nb2/3)O-3 and similar ferroelectric relaxors which never truly become ferroelectric at zero-field, disordered Pb(Sc1/2Ta1/2)O-3 (PST) is a relaxer that spontaneously transforms into a ferroelectric phase. The control of the degree of order o ...
The piezoelectric properties of lead zirconate titanate (PZT) thin films deposited on thick silicon substrates and thin silicon membranes were investigated using optical interferometry. The effect of the geometrical constraints and clamping effects on the p ...
Pb(Sc1/2Ta1/2)O-3 ceramics have been characterized by dielectric measurements in a wide range of frequencies (10(2)-10(9) Hz). A strong dispersion occurs with two low and high frequency contributions below the transition temperature. Only high frequency re ...
Using a first-principles approach, we calculate Si 2p core-level shifts for spherosiloxane H8Si8O12 clusters chemisorbed on Si(001). A chemisorption mechanism that preserves the cage structure of the clusters is assumed. The resulting relaxed surface struc ...
