Ferroelectric solid solutions with morphotropic boundaries: Vanishing polarization anisotropy, adaptive, polar glass, and two-phase states

摘要: The generic case of a ferroelectric solid solution is considered wherein different symmetry phases located at opposing ends the diffusionless phase diagram are separated by morphotropic boundary (MB). It shown that Landau theory weak first-order transformations automatically predicts vanishing anisotropy polarization, continuity thermodynamic properties, and drastic decrease in domain wall energy near MB line results formation adaptive nanodomain states. Low-resolution diffraction from these states acquired coherence lengths elastic x-ray or neutron scattering probes will produce same pattern as attributed to monoclinic (MA,MB,MC) phases. further electric- stress-field-induced reconfiguration softening piezoelectric, elastic, dielectric properties line. In addition, spherical degeneration polarizat...