Theory of phase transitions in second-order ferroelectric films: effects of surfaces and surface-induced stresses on polarization
Document Type
Article
Publication Date
1-1-2002
Abstract
The Landau-Devonshire theory is used to study the inter-relationship between polarization and stress in a second-order ferroelectric thin film, where both polarization and stress are in-plane. The intrinsic effects of surfaces and surface-induced stresses on polarization are considered by the introduction of extrapolation lengths in the formulation. Numerical calculations are made for a freestanding ferroelectric film, which is symmetric with respect to mid plane. The study is performed under the assumption that the polarization is enhanced or suppressed near the film surface. For a film with polarization enhanced near the surface, it is assumed that the surface tends to expand thus inducing a surface-tensile stress ('tensile' surface). Surface-induced compressive stress is assumed to exhibit in surface with polarization suppressed near surface ('compressive' surface) It is shown that a diminishing film size (thickness) has a strong influence on polarization and stress. (C) 2002 Elsevier Science Ltd. All rights reserved.
Keywords
Ferroelectrics, Thin Films, Phase Transitions
Divisions
PHYSICS
Publication Title
Solid State Communications
Volume
123
Issue
10
Additional Information
Department of Physics, Faculty of Science Building, University of Malaya, 50603 Kuala Lumpur, MALAYSIA