Origins of the macroscopic symmetry breaking in centrosymmetric phases of perovskite oxides
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It is shown that a strong but diffuse dielectric anomaly, commonly expected only in disordered ferroelectrics, may be inherent in strained and defect-free perovskite ferroelectric thin films. The origin of this unusual anomaly, which was never predicted fo ...
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The ferroelectric transition of bulk strontium titanate is suppressed by a combination of two effects: (1) the structural changes produced by the antiferrodistortive transition at T-a =105 K and (2) the quantum fluctuations. The structural changes are stro ...
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Using Landau-Ginzburg-Devonshire theory and tetragonal BaTiO3 as an example, this letter demonstrates that strong electric bias fields applied antiparallel to spontaneous polarization may lead to a large enhancement of piezoelectric properties in monodomai ...
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 ...
A strong de electric field dependence of the dielectric permittivity makes perovskite ferroelectrics promising materials for tunable microwave devices like phase shifters, tunable resonators, tunable filters etc. Dielectric loss is a crucial parameter for ...
The structure of the antiphase domain boundaries of strontium titanate SrTiO3 that exist at temperatures below the antiferrodistortive transition, is analyzed. It is found that some boundaries are similar to Neel domain walls, as an additional component of ...
