Electric Field Induced Cubic to Monoclinic Phase Transition in Multiferroic 0.65Bi(Ni1/2Ti1/2)O3-0.35PbTiO3 Solid Solution

TL;DR

This study demonstrates an electric field-induced phase transition from cubic to monoclinic in a multiferroic solid solution, with significant lattice strain and electromechanical coupling, revealed through XRD analysis.

Contribution

It provides new insights into electric field-driven phase transitions in multiferroic materials, specifically showing a cubic to monoclinic transition at a critical electric field.

Findings

Cubic structure transforms to monoclinic at ≥5kV/cm electric field.

Large c-axis lattice strain (1.6%) achieved at 30kV/cm.

Drastic change in lattice parameters correlates with electric field strength.

Abstract

The results of x-ray diffraction (XRD) studies on 0.65Bi(Ni1/2Ti1/2)O3-0.35PbTiO3 solid solution poled at various electric field is presented. After poling, significant value of planar electromechanical coupling coefficient (kP) is observed for this composition having cubic structure in unpoled state. The cubic structure of 0.65Bi(Ni1/2Ti1/2)O3-0.35PbTiO3 transforms to monoclinic structure with space group Pm for the poling field greater than equal to 5kV/cm. Large c-axis microscopic lattice strain (1.6 %) is achieved at 30 kV/cm poling field. The variation of the c-axis strain and unit cell volume with poling field show a drastic jump similar to that observed for strain versus electric field curve in (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 and (1-x)Pb(Zn1/3Nb2/3)O3-xPbTiO3.