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The experimentally observed temperature dependence of the quartic coefficients in the Landau-Devonshire expansion for BaTiO3 is naturally accounted for within a proper fluctuation model. It is explained, in particular, why one of the quartic coefficients v ...
The continuous downscaling of microelectronic circuits combined with increasing interest in ferroelectric thin films for non-volatile random access memories (FeRAM) is drawing great attention to small ferroelectric thin film structures. There are various c ...
Piezoelectric response nonlinearity is approached using the Preisach description of hysteretic systems as collection of distributed bistable units. The Preisach model and its recent physical interpretation in terms of moving domain wall in a stochastically ...
The present study aims at a better understanding of the high piezoelectric properties encountered in lead-based ferroelectrics by focusing on the extrinsic contributions to the response. The main characteristics of these materials are the highly nonlinear ...
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 ...
Novel design of an integrated digital refelction-type phase shifter based on a Barium Strontium Titanate thin-film capacitor is presented. Measured characteristics of the phase shifter am compared with the theoretically predicted ones. ...
The contribution from the irreversible displacement of non-180 degrees domain walls to the direct longitudinal piezoelectric d(33) coefficient of BaTiO3 and Pb(Zr,Ti)O-3 ceramics was determined quantitatively by using the Rayleigh law. Effects of the cryst ...
It is shown that at weak alternating stress the relationship between the piezoelectrically induced charge and applied stress in ferroelectric ceramics has the same form as the Rayleigh law for magnetization versus magnetic field in ferromagnetic materials. ...
Thickness mode resonances in commercial piezoelectric ceramics have been characterised as a function of frequency by two methods. The first is based on a fit on the electrical impedance for the fundamental and the overtones. This method has been applied to ...
The most significant advance in this field in the past year has been the demonstration that single-crystal langasite, La3Ga5SiO14, can be used, at least at high frequencies, at temperatures up to 1000 degrees C. New evidence suggests that domain-wall contr ...
