Effect of Mechanical Boundary Conditions on Phase Diagrams of Epitaxial Ferroelectric Thin Films

✍ Scribed by Pertsev, N. A.; Zembilgotov, A. G.; Tagantsev, A. K.

• Book ID: 121503161
• Publisher: The American Physical Society
• Year: 1998
• Tongue: English
• Weight: 121 KB
• Volume: 80
• Category: Article
• ISSN: 0031-9007
• DOI: 10.1103/PhysRevLett.80.1988

✦ Synopsis

A phenomenological thermodynamic theory of ferroelectric thin films epitaxially grown on cubic substrates is developed using a new form of the thermodynamic potential, which corresponds to the actual mechanical boundary conditions of the problem. For single-domain BaTiO 3 and PbTiO 3 films, the "misfit-temperature" phase diagrams are constructed. It is found that the 2D clamping of the films, apart from a shift of the temperature of the ferroelectric transition, results in a change of its order. A change of the sequence of the phases and the appearance of phases forbidden in the bulk crystals are predicted. [S0031-9007(98)05421-0]