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We develop a theory for investigating atomic-scale dielectric permittivity profiles across interfaces between insulators. A local susceptibility chi(x;omega) is introduced to describe variations of the dielectric response over length scales of the order of ...
Nonlinear dielectric response of soft and hard PZT is experimentally studied at subswitching conditions. The correlations between defect disordering and parameters of nonlinear dielectric response and hysteresis are demonstrated and discussed. (c) 2005 Els ...
Most of the known self-assembly processes occur in solution, where nanosized objects interact each other forming new structures. Their real-time characterization in terms of the size and optical properties of these objects is vital for understanding those ...
A theoretical study on the effect of spontaneous polarization screening on the dielectric response of ferroelectric films with 180 degrees domains going through the film thickness (through-domains) is presented. It has been shown by several researchers tha ...
Echo volumar imaging (EVI) is a 3D modification of echo-planar imaging (EPI) that allows data from an entire volume to be acquired following a single RF excitation. EVI provides a high rate of volumar data acquisition, which is advantageous for functional ...
Hysteretic and nonlinear dielectric behaviour in ferroelectric ceramics has been of interest since 1950s, when these materials found application in various electronic devices. Presently, these phenomena concern with important areas of science, technology a ...
L2,3 x-ray absorption spectra of aq. [RuII(bpy)3]2+ were recorded in its ground and excited states, 50 ps after short pulse laser excitation. Significant changes in both the XANES (x-ray Near-Edge Absorption Structure) and the EXAFS (Extended x-ray Absorpt ...
We present a novel approach that allows us to calculate the dielectric response of periodic systems in the quantum Monte Carlo formalism. We employ a many-body generalization for the electric-enthalpy functional, where the coupling with the field is expres ...
We study the infrared properties of the Si-SiO2 interface within a first-principles approach. In order to provide an atomic-scale description of the dielectric permittivity (both high-frequency and static) and of the infrared absorption at the interface, w ...
The influence of the uniaxial bias stress on the piezoelectric properties of tetragonal BaTiO3 and PbTiO3 monodomain crystals is modeled in the framework of the phenomenological Landau-Ginzburg-Devonshire theory. It is shown that tensile and compressive st ...