Composition-dependent polarization switching behaviors of (111)-preferred polycrystalline Pb(Zr_{x}Ti_{1-x})O_{3} thin films

We investigated the time-dependent polarization switching behaviors of (111)-preferred polycrystalline Pb(ZrxTi1-x)O3 thin films with various Zr concentrations. We could explain all the polarization switching behaviors well by assuming Lorentzian distributions in the logarithmic polarization switching time [Refer to J. Y. Jo et al., Phys. Rev. Lett. (in press)]. Based on this analysis, we found that the Zr ion-substitution for Ti ions would induce broad distributions in the local field due to defect dipoles, which makes the ferroelectric domain switching occur more easily.

Domain Switching Kinetics in Disordered Ferroelectric Thin Films

We investigated domain kinetics by measuring the polarization switching behaviors of polycrystalline Pb(Zr,Ti)O$_{3}$ films, which are widely used in ferroelectric memory devices. Their switching behaviors at various electric fields and temperatures could be explained by assuming the Lorentzian distribution of domain switching times. We viewed the switching process under an electric field as a motion of the ferroelectric domain through a random medium, and we showed that the local field variation due to dipole defects at domain pinning sites could explain the intriguing distribution.