Modeling of Interface Dielectric Constant in Nanodielectrics

In the continuing bid to understand the nature of the interface surrounding each nanoparticle in a nanodielectric, Electrostatic Force Microscopy (EFM) has been employed by researchers in the recent past. The authors recently developed a Finite Element Method (FEM)-based model to computationally obtain the EFM phase shift images of the region around an isolated particle in a nanodielectric. This model was used in conjunction with extensive experimental data to estimate the dielectric constant of the interface and its thickness. In this work, this model is extended to study the possibility of an interface in which the dielectric constant varies across the interface thickness. The dielectric constant is modeled as a linear function of distance from the nanoparticle for the estimated interface thickness. Comparison with experimental data is seen to support this hypothesis.