MS27-05 - Phase Transitions in Zr-Rich Lead Zirconate-Titanate Studied by Single Crystal Diffuse and Inelastic X-Ray Scattering


Daria Andronikova (Ioffe Institute, Russia)

Lead zirconate-titanate (PbZr1−xTixO3, PZT) is a piezoelectric perovskite material, which possesses ferroelectric as well as antiferroelectric properties. Thanks to high piezoelectric coefficient PZT is broadly used in many electronic devices [1].

For PZT with 0 < x < 0.06 antiferroelectric phase is stable at room temperature. This phase has an orthorhombic structure resulting from antiparallel displacements of lead ions and opposite rotations of ZrO6 octahedrals for the neighboring layers of paraelectric cubic perovskite structure [2]. Thus, phase transition into the antiferroelectric phase is associated with condensation of two phonon modes with different symmetry. In paraelectric phase dielectric measurements [3] revealed critical divergence of dielectric constant, which could be associated with ferroelectric mode instability in Brillouin zone center. There is ferroelectric intermediate phase in-between the antiferroelectric and paraelectric phases. Electron diffraction indicates that the intermediate phase has incommensurate modulated structure [4], however, the symmetry of this phase is still not well understood.

To study microscopic mechanism resulting in PZT phase transitions the measurements of single crystal diffuse and inelastic X-ray scattering in PZT with 0.007 < x < 0.04 have been performed.  In the present contribution, the relevant critical dynamics accompanying phase transitions in Zr-rich PZT will be discussed using obtained results.

Andronikova D. acknowledges support by Russian President Grants No. SP-3762.2018.5


[1] Haertling G. H. JACS, 82, 4, 1999
[2] Fujishita H., JPSJ, 53,1 1984
[3] Roleder K. Phase Transitions, 71, 287, 2000
[4] Watanabe S. PRB, 66, 2002