Enhanced dielectric and ferroelectric responses in La3+/Ti4+ co-substituted SrBi2Ta2O9 Aurivillius phase

Infrared activity in the Aurivillius layered ferroelectric SrBi2Ta2O9

Experimental studies were carried out on infrared-active phonons in the Aurivillius ferroelectric SrBi2Ta2O9 ~SBT!, using reflectivity measurements ~down to 200 cm! and transmission measurements ~down to 100 cm! on crystals, pellets, and thin films. An analysis was done of the contrasting consequences of the competing orthorhombic and pseudotetragonal symmetries in SBT. Reflectivity results for...

Cobalt-Substituted Seven-Layer Aurivillius Bi8Fe4Ti3O24 Ceramics: Enhanced Ferromagnetism and Ferroelectricity

In this work, Aurivillius-phase Bi8Fe4-xCoxTi3O24 (7-BFCT, 0 ≤ x ≤ 0.4) powders and ceramics were successfully prepared by the combination of citrate combustion and hot-press methods. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) indicate a successful synthesis of the pure phase of the 7-BFCT ceramics, and all the samples showed a good seven-layer structur...

Dielectric behaviors of Aurivillius Bi5Ti3Fe0.5Cr0.5O15 multiferroic polycrystals: Determining the intrinsic magnetoelectric responses by impedance spectroscopy

Bismuth layer ferroelectrics (BLFs) pioneered by Aurivillius about sixty years ago have been revived recently because of the fatigue- and lead-free behaviors and high Curie temperature, and especially the robust magnetoelectric (ME) effect. However, discerning the intrinsic ME nature, and the inherence between charged defect dipole induced relaxation and spin-related behaviors are still an ardu...

Tailoring dielectric properties of ferroelectric-dielectric multilayers

Piezoelectricity in the dielectric component of nanoscale dielectric-ferroelectric superlattices.

The origin of the functional properties of complex oxide superlattices can be resolved using time-resolved synchrotron x-ray diffraction into contributions from the component layers making up the repeating unit. The CaTiO3 layers of a CaTiO3/BaTiO3 superlattice have a piezoelectric response to an applied electric field, consistent with a large continuous polarization throughout the superlattice...