Domain structures and phase transitions of the relaxor-based piezo-/ ferroelectric (1-x)Pb(Zn1/3Nb2/3)O-3-xPbTiO(3) single crystals

The domain structures and phase transitions of the relaxer-based piezo-/ fe rroelectric (1-x)Pb(Zn1/3Nb2/3)O-3-xPbTiO(3) single crystals, grown from hi gh temperature solutions, have been studied by polarized light microscopy. The PZN crystals show domains of trigonal symmetry and a diffused phase tra nsition of relaxer type. The PZNT91/9 (x=0.09) crystals exhibit complex dom ain structures with coexistence of the trigonal and tetragonal domains at r oom temperature, resulting from a distribution of Ti4+ concentration in the individual domains. The domain structures, the sequence and temperature of phase transitions have been interpreted in relation to the morphotropic ph ase boundary (MPB) behavior of the PZN-PT system. It is shown that analysis of the domain structure and in situ studies of local phase transition prov ide valuable information on the chemical composition and properties of the PZNT crystals around MPB. This information will have relevance to the elect romechanical transducer applications of these innovative piezocrystals.