PbTiO₃, with ABO₃ non-centrosymmetric perovskite structure, is a classical ferroelectric material with high spontaneous electric polarization, while CoTiO₃, with ABO₃ centrosymmetric ilmenite structure, presents antiferromagnetic order below 30 K. The atomic substitution of Pb²⁺ by Co²⁺ forming lead to the formation of a solid solution for x up to 10% and a composite between 10 and 96%[1-3] The magnetoelectric property of a material needs the both, centrosymmetric for magnetic order and non-centrosymmetric for ferroelectricity, which can be found normally in complex structures like quadruple perovskites.

In the present work were studied polycrystalline samples of Co_xPb_1-xTiO₃ synthesized by solid state reaction, for x ranging from 0.0 to 1.0, using Raman scattering and X-ray diffraction (LNLS-Campinas) under high hydrostatic pressure. The XRD data permitted to determine the compressibility, bulk modulus and it first derivative at P=0 while the Raman scattering results showed that the currently accepted tetragonal-ferroelectric to the cubic-paraelectric phase transition of PbTiO₃ phase does not occur completely since the E(1TO) soft mode wavenumber blue-shift is recovered for pressures above 10 GPa.

1- T.R. Cunha, A.G. Rodrigues, J.E. Rodrigues…

Solid State Science vol. 88, pg 1-5 (2019)

2- T.R. Cunha, A.G. Rodrigues, J.E. Rodrigues…

Material Research Bulletin vol. 107, pg. 462-467 (2018)

3- R.C. da Costa, J.E. Rodrigues, A.J. Gualdi…

Journal of Alloys and Compounds vol. 739, pg. 600-606 (2018).