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The physical origin of the piezoelectric effect has been the focus of much research work. While it is commonly accepted that the origins of piezoelectricity may be intrinsic (related to the change of lattice parameters) and extrinsic (related to the movement of domain walls), their separation is often a challenging experimental task. Here in situ high‐resolution synchrotron X‐ray diffraction has been combined with a new data analysis technique to characterize the change of the lattice parameters and domain microstructure of a PbZr1−xTixO3 (x = 0.45) crystal under an external electric field. It is shown how `effective piezoelectric coefficients' evolve upon the transition from purely `intrinsic' effects to `extrinsic' ones due to domain‐wall motion. This technique and corresponding data analysis can be applied to broader classes of materials and provide important insights into the microscopic origin of their physical properties. [ABSTRACT FROM AUTHOR]

LaF3/SrF2multilayer heterostructures with thicknesses of individual layers in the range 5–100 nm have been grown on MgO(100) substrates using molecular beam epitaxy. The longitudinal conductivity of the films has been measured using impedance spectroscopy in the frequency range 10−1–106 Hz and a temperature range 300–570 K. The ionic DC conductivities have been determined from Nyquist impedance diagrams and activation energies from the Arrhenius–Frenkel equation. An increase of the DC conductivity has been observed to accompany decreased layer thickness for various thicknesses as small as 25 nm. The greatest conductivity has been shown for a multilayer heterostructure having thicknesses of 25 nm per layer. The structure has a conductivity two orders of magnitude greater than pure LaF3bulk material. The increasing conductivity can be understood as a redistribution of charge carriers through the interface due to differing chemical potentials of the materials, by strong lattice-constant mismatch, and/or by formation of a solid La1-xSrxF3-xsolution at the interface during the growth process. [ABSTRACT FROM PUBLISHER]

Synchrotron X-rays on the Swiss Norwegian Beamline and BM28 (XMaS) at the ESRF have been used to record the diffraction response of the PMN-PT relaxor piezoelectric 67% Pb(Mg1/3Nb2/3)O3-33% PbTiO3 as a function of externally applied electric field. A DC field in the range 0-18 kV cm−1 was applied along the [001] pseudo-cubic direction using a specially designed sample cell for in situ single-crystal diffraction experiments. The cell allowed data to be collected on a Pilatus 2M area detector in a large volume of reciprocal space using transmission geometry. The data showed good agreement with a twinned single-phase monoclinic structure model. The results from the area detector were compared with previous Bragg peak mapping using variable electric fields and a single detector where the structural model was ambiguous. The coverage of a significantly larger section of reciprocal space facilitated by the area detector allowed precise phase analysis. [ABSTRACT FROM AUTHOR]