Origin Of the enhanced flexoelectricity of relaxor ferroelectrics

Abstract

We have measured the bending-induced polarization of Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystals with compositions at the relaxor-ferroelectric phase boundary. The crystals display very large flexoelectricity, with flexocoupling coefficients an order of magnitude bigger than the theoretical upper limit set by the theories of Kogan and Tagantsev. This enhancement persists in the paraphrase up to a temperature T* that coincides with the start of elastic softening in the crystals. Analysis of the temperature dependence and cross-correlation between flexoelectric, dielectric and elastic properties indicates that the large bendinginduced polarization of relaxor ferroelectrics is not caused by intrinsically giant flexoelectricity, but by the reorientation of polar nanotwins that become ferroelastically active below T*.

References in corpus (4)

• Strain gradient induced polarization in SrTiO3 single crystals
• First-principles theory and calculation of flexoelectricity
• Flexoelectricity from density-functional perturbation theory
• Room temperature surface piezoelectricity in SrTiO3 ceramics via piezoresponse force microscopy

Cited by in corpus (9)

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• Nonlinear dynamics of polar regions in paraelectric phase of (Ba1-x,Srx)TiO3 ceramics
• Twin Boundary Mediated Flexoelectricity in LaAlO${}_3$
• Screening piezoelectricity in determination of flexoelectric coefficient at nanoscale
• Phase transition and polar cluster behavior above Curie temperature in ferroelectric BaTi${}_{0.8}$Zr${}_{0.2}$O${}_3$
• Microscopic flexoelectricity in the canonical PMN relaxor