A Phase Diagram for Epitaxial PbZr1−xTixO3 Thin Films at the Bulk Morphotropic Boundary Composition
Abstract:A phase diagram of temperature versus strain was constructed for a (001)-oriented PbZr1−xTixO3 epitaxial single crystal thin film near the bulk morphotropic boundary composition (x=0.47) on an (001)-oriented cubic substrate. The phase-field approach is employed. It is shown that a mixture of distorted rhombohedral, orthorhombic, and tetragonal phases exists under small values of strain, i.e., close to the in-plane clamped boundary condition. This result contradicts thermodynamic calculations assuming a single-domain state that predicted a single distorted rhombohedral phase under similar strains. Furthermore, it is demonstrated that under a large tensile strain current phase-field simulations showed a tetragonal phase with a1/a2 twin structures as the stable state whereas thermodynamic calculations predicted an orthorhombic phase.
Document Type: Research Article
Affiliations: Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802
Publication date: June 1, 2005