Research project: Phenomenological studies of compositionally graded ferroelectric superlattices consisting of novel solid solution system

The compositionally graded ferroelectric based on a lead-free solid solution system such as BaxSr1-xTiO3 can exhibit large polarization gradients and desirable temperature-stable susceptibilities. This novel solid solution not only in compliance with the future lead-free trend but also meet the requirement of a large piezoelectric response of ferroelectrics for modern electronic applications. By tailoring their composition at the atomic level, we can manipulate the physical properties and functionalities of compositionally graded ferroelectric. Hence, this research is to develop a thermodynamic model based on the Landau-Ginzburg theory to study the fundamental physical properties of compositionally graded ferroelectric superlattices by considering the interface effect. A theoretical study on the fundamental physical properties is very crucial in the fabrication of compositionally graded ferroelectric superlattices for technological applications, for instance: transducers, high permittivity dielectrics, pyroelectric sensors, piezoelectric devices, tunable ferroelectric capacitor et al.