Argonne National Laboratory, Argonne, Illinois 60439, USA.
Phys Rev Lett. 2010 Oct 15;105(16):167601. doi: 10.1103/PhysRevLett.105.167601. Epub 2010 Oct 12.
Polarization switching in ferroelectrics has been thought to occur only through the nucleation and growth of new domains. Here we use in situ synchrotron x-ray scattering to monitor switching controlled by applied chemical potential. In sufficiently thin PbTiO₃ films, nucleation is suppressed and switching occurs by a continuous mechanism, i.e., by uniform decrease and inversion of the polarization without domain formation. The observed lattice parameter shows that the electric field in the film during switching reaches the theoretical intrinsic coercive field.
铁电体中的极化翻转被认为仅通过新畴的成核和生长来发生。在这里，我们使用同步辐射 X 射线散射原位监测由外加化学势控制的开关。在足够薄的 PbTiO₃ 薄膜中，成核被抑制，并且通过连续机制发生开关，即通过极化的均匀减小和反转而不形成畴。观察到的晶格参数表明，在开关过程中薄膜中的电场达到了理论的固有矫顽场。
