Macroscopic lamellar heterophase pattern in Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystals

The paper describes lamellar heterostructures, observed in (1 - x) Pb(Mg1/3Nb2/3)O(3-)xPbTiO(3) (PMN-xPT) single crystals with x = 0.32. These lamellas are naturally formed in single crystals cooled under bias electric field applied along [001](pc) and then zero-field heated to the vicinity of the so-called depoling temperature T-RT, but similar structures were also encountered at ambient conditions. The polarization dependence of the Raman scattering intensities was employed to demonstrate that these lamellar structures are composed of tetragonal-like and rhombohedral-like layers extending over macroscopic (mm) lengths. The properties and interest of these macroscopic heterophase interfaces are discussed.