Atomic-resolution analysis of polar structure of PbTiO₃ thin film

Abstract

The atomic-resolution TEM analysis of the structure and the polarity of 90˚ domain of PbTiO3/SrTiO3 epitaxilal film was conducted. The domain wall has finite thickness about 1.5nm. In the wall, the lattice is strained and has lower symmetry than tetragonal phase, however, the polarization has the almost same orientation as the inside of the domain. The polarization rotation takes place just at the center of the wall through only one atomic layer.