EFFECT OF DEPOLARIZING FIELD AND CHARGED DOPANTS ON POLARIZATION IN POLYCRYSTALLINE Pb(ZrTi)O₃ FILM

ABSTRACT

A two-dimensional model taking into account the reciprocal effect of electric field on polarization as well as variation of the polarization from saturated to minor hysteresis loops is developed for polycrystalline Pb(ZrTi)O₃(PZT) film, where ferroelectric PZT grains are separated by ultrathin semiconductor PbO interlayers. Using the model, it is shown that the depolarizing field, produced by uncompensated polarization charge, strongly depresses the polarization not only on grain boundaries but at appreciable distance inside the grain. The charged dopants in the film cannot suppress the depolarizing field. Instead, the dopants strengthen the coordinate dependency of the polarization along the grain.

Keywords:

• Polarization charge
• grain boundary
• depolarizing field
• polarization

ACKNOWLEDGMENTS

The study was supported by the Program of the Presidium of the RAS “The basis of fundamental study of nanotechnologies and nanomaterials”, and the Program of the RAS, project “Strong Correlated Electrons in Semiconductors, Metals, Superconductors and Magnetic Materials”.