Electric fields in ferroelectric polymer metal structures; modeling using a finite element boundary element method

Significant advances in ferroelectric polymers used in electromechanical-active transduction-sensor applications, as well as strong interest in special capacitive structures involving ferroelectric metal complex structures, have occurred very recently. The applications, initially oriented toward military use, such as surveillance systems for underwater detection and large area hydrophone arrays, have spread to high-voltage engineering, transducers for robotics, advanced nonlinear capacitors, and other civilian applications. In order to reach the optimum of such devices, higher electric fields must be employed, leading to the need for a very accurate modeling, not only of the steady state distribution of the electric fields, but, much more importantly, the transient behavior of such fields in the presence of the highly nonlinear, ferroelectric, polymer media. A finite element method (FEM) using Galerkin´s method, coupled with a boundary element method (BEM) numerical code, are described in this paper as a device for a precise modeling in space and time. The formulation presented for nonlinear, nonhomogeneous media can be extended readily to accommodate material anisotropy by specifying ||ε|| as a tensor. Several practical examples and applications are presented