Domain evolution and polarization of continuously graded ferroelectric films

Alexander Roytburd, Victor Roytburd
2010 Philosophical Magazine  
A thermodynamic analysis of graded ferroelectric films demonstrates that in the equilibrium state the films are subdivided into a single-domain band and a polydomain band which consists of wedge-shape domains. Polarization under an external electrostatic field proceeds through an inter-band boundary movement due to growth or shrinkage of the wedge domains. It is shown how the domain structure and evolution are determined by the principal characteristics of the film: the distribution of the
more » ... ibution of the spontaneous polarization and dielectric constant. Graded films exhibit a sharp increase of polarization with the field for weak fields, with a drop of the dielectric constant when the field is increasing. A general approach to finding the dependence of the displacement and the wedgedomain shape on the field as well as analytical solutions for the p 4 Landau-Devonshire and parabolic potentials are presented.
doi:10.1080/14786430903147098 fatcat:bubw7it7rva3nnvawmecuh3zye