Evolution of nanodomains in 0.9PbMg1/3Nb2/3O3-0.1PbTiO3 single crystals

High-resolution studies of polar structures have been performed on the 0.9Pb(Mg1/3Nb2/3)O3-0.1PbTiO3 (0.9PMN-0.1PT) single crystals by piezoresponse force microscopy. A complex pattern of nanosized polar regions (nanodomains) was observed above the temperature of the structural phase transition. Autocorrelation function technique applied to the analysis of the obtained images revealed clear self-organization of the nanodomains in (110) crystallographic directions and allowed estimating their mean size (∼70 nm at room temperature). Upon heating, the gradual decay of the piezoresponse contrast took place, however, the nanodomains could be still observed at temperatures as high as 385 K. The nature of the observed phenomena is attributed to a peculiar transient state between relaxor and ferroelectric, which developed near the crystal’s surface.