Low-temperature electrical characteristics of Bi3.15Nd0.85Ti3O12 thin films

Ferroelectric and dielectric characteristics of Bi3.15Nd0.85Ti3O12 ferroelectric thin films were studied at temperatures from 296 down to 100K. The temperature dependence of these characteristics was discussed in terms of the Rayleigh model. Although the Rayleigh law fits well the dielectric data below 140K, it cannot describe the data at higher temperatures, where a mechanism contributes to the dielectric constant without producing losses. This mechanism may probably be related to bending of domain walls pinned by two nearest obstacles. The contribution from such bending is frozen out at low temperatures due to enhanced domain pinning.