Abstract
We have investigated domain structures in the monoclinic phase near the MPB region of (1-x)PMN-xPT with x~0.32 by a ttransmission electron microscopy experiment. In addition to the large plate-shaped domains with the 100~200 nm width, we found a nanoscaled lamella-type domain structures with ~10 nm width inside the large plate-shaped domains. We checked various electron diffraction patterns at 298 K and no superlattice spots due to the chemical ordering with the Mg:Nb=1:1 ratio can be seen in 0.68PMN-0.32PT, unlike in PMN. In-situ TEM observation of changes of the domain structures as a function of the temperature was carried out and revealed that the complicated domain configuration is inherent to the monoclinic phase in the MPB region.
