Electric-field-induced structural transition of a single crystal Pb(Zn 1/3 Nb 2/3 )O 3 -8%PbTiO 3 grown in the ͑001͒ direction was studied by use of Raman scattering spectroscopy. By comparing the changes in Raman spectra induced by the electric field with the temperature-dependent changes, we could confirm that the structural transition to tetragonal phase is initiated at a threshold electric field E c1 and completed at higher transition field E c2 . In the electric-field range from E c1 to E c2 , it is found that rhombohedral and tetragonal phases coexist. The lower threshold field E c1 is found to coincide with the field at which the strain rises abruptly in the strain electric-field hysteresis loop while the upper threshold field E c2 corresponds to the electric field where a slope change is observed in the high-field saturation region beyond the hysteresis loop.

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Lead magnesium niobate-lead titanate [Pb(Mg 1/3 Nb 2/3 )O 3 (PMN)-PbTiO 3 (PT)] films were synthesized using pulsed laser deposition, and the effect of substrates on the deposition behavior of the PMN-PT film was investigated. Phase evolution of PMN-PT thin films was found to depend significantly on the type of the substrate used during deposition. Though a mixture of pyrochlore and perovskite was observed when films were deposited on a Pt/TiO 2 /SiO 2 /Si substrate, the oxide substrates, such as (Ba 0.5 Sr 0.5 )RuO 3 /Si, SrTiO 3 , and LaAlO 3 , enabled the deposition of pure perovskite. Scanning Auger microprobe, transmission electron microscope, and x-ray diffraction analysis showed that an interfacial layer between the substrates and the oxide film was central to the phase evolution behavior. On the Pt/TiO 2 /SiO 2 /Si substrate, an interfacial layer of lead-platinum (Pb-Pt) played a major role in the formation of the pyrochlore phase. However, on oxide substrates, there was no interfacial layer and interdiffusion of A-site cations was observed between the PMN film and the oxide electrodes.