Effects of multi-surface modification on Curie temperature of ferroelectric films

Abstract

Within the framework of mean field theory, we study the effects of multi-surface modification on the Curie temperature of ferroelectric films using the transverse Ising model. The general nonlinear equations for Curie temperature of multi-surface ferroelectric films with arbitrary exchange constants and transverse fields are derived by the transfer matrix method. As an example, we consider an (l,n,l) film consisting of l top surface layers, n bulk layers and l bottom surface layers. Two types of surface modification, modifications of a surface exchange constant and a surface transverse field, are taken into account. The dependence of Curie temperature on the surface layer numbers, bulk layer numbers, surface exchange constants, surface transverse fields and bulk transverse fields is discussed.