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A possible anomaly in the temperature dependence of nonlinear dielectric susceptibility chi(nl) of relaxor ferroelectrics related with the freezing phase transition was investigated. First, based on the phenomenological approach, the anomaly in the chi(nl) ...
It is shown that the effects of large de bias and ac driving fields on the dielectric permittivity of single crystals of PbMg1/3Nb2/3O3 (PMN) relaxer ferroelectric exhibit very different behavior, including anisotropy and sign of the effect, which is trace ...
The size, shape, and polarization orientation of fatigued areas formed during the suppression of the switchable polarization (P-r(s)) (fatigue) in Ft-FZT-Pt ferroelectric capacitors (FECAPs), were observed by means of atomic force microscopy and by imaging ...
Fatigue phenomena occurring in Pb(ZrxTi1-x)O-3 ferroelectric thin-film capacitors (FECAP) with Pt electrodes are studied by means of conduction measurements in the cold-field-emission (tunneling) regime. We have determined that conduction in virgin FECAPs ...
It was recently suggested, basing on the analysis of a wide range of macroscopic experimental results([1-4]), that fatigue in ferroelectric thin film capacitors, particularly in the case of PZT with metallic electrodes (Pt), must be related to the freezing ...
A simple and reliable method which allows one to distinguish between the two major microscopic scenarios for the suppression of the switching polarization (P-r(s)), i.e., pinning of ferroelectric domain walls (DWs) through the Pb(Zr,Ti)O-3 film (PZT) (bulk ...
The dielectric response of the relaxer ferroelectric PbMg1/3Nb2/3O3 (PMN) is found to be a non-analytical function of the ac field, with the absolute value of the non-linear component of the polarization given by \P-nl\ alpha E-m(gamma(omega,T)). The depen ...
The contribution of domain walls to the dielectric permittivity of ferroelectrics is customarily explained by the model of locally pinned walls. Here we analyze the complementary case and calculate wall contribution to permittivity of a sample in which 180 ...
A surprising non-cumulative effect of the degradation mechanism (fatigue) of the switched polarization (P-r(s)), was observed in MOCVD and sol-gel prepared Pb(Zr0.47Ti0.53)O-3 (PZT) ferroelectric thin films capacitors (FECAP) with Pt-electrodes. This effec ...
A phenomenological thermodynamic theory of ferroelectric thin films epitaxially grow on cubic substrates is developed using a new form of the thermodynamic potential. which corresponds to the ac tual mechanical boundary conditions of the problem, For singl ...
