Polarization states of polydomain epitaxial Pb(Zr1-xTix)O3 thin films and their dielectric properties

Abstract

Ferroelectric and dielectric properties of polydomain (twinned) single-crystal Pb(Zr1-xTix)O3 thin films are described with the aid of a nonlinear thermodynamic theory, which has been developed recently for epitaxial ferroelectric films with dense laminar domain structures. For Pb(Zr1-xTix)O3 (PZT) films with compositions x = 0.9, 0.8, 0.7, 0.6, 0.5, and 0.4, the "misfit strain-temperature" phase diagrams are calculated and compared with each other. It is found that the equilibrium diagrams of PZT films with x > 0.7 are similar to the diagram of PbTiO3 films. They consist of only four different stability ranges, which correspond to the paraelectric phase, single-domain tetragonal ferroelectric phase, and two pseudo-tetragonal domain patterns. In contrast, at x = 0.4, 0.5, and 0.6, the equilibrium diagram displays a rich variety of stable polarization states, involving at least one monoclinic polydomain state. Using the developed phase diagrams, the mean out-of-plane polarization of a poled PZT film is calculated as a function of the misfit strain and composition. Theoretical results are compared with the measured remanent polarizations of PZT films grown on SrTiO3. Dependence of the out-of-plane dielectric response of PZT films on the misfit strain in the heterostructure is also reported.

23 pages, 4 figures

References in corpus (7)

• Monoclinic and triclinic phases in higher-order Devonshire theory
• Ab initio study of ferroelectric domain walls in PbTiO3
• Ferroelectricity in ultra-thin perovskite films
• Ultrathin films of ferroelectric solid solutions under residual depolarizing field
• Thermodynamic theory of epitaxial ferroelectric thin films with dense domain structures
• Polarization Instability in Polydomain Ferroelectric Epitaxial Thin Films and the Formation of Heterophase Structures
• Very large dielectric response of thin ferroelectric films with the dead layers

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