Macroscopic lamellar heterophase pattern inPb(Mg1/3Nb2/3)O3−PbTiO3single crystals

The paper describes lamellar heterostructures, observed in $(1\ensuremath{-}x)\text{Pb}({\mathrm{Mg}}_1/3{\mathrm{Nb}}_2/3){\mathrm{O}}₃\text{\ensuremath{-}}x{\mathrm{PbTiO}}₃$ (PMN-$x\text{PT}$) single crystals with $x=0.32$. These lamellas are naturally formed in single crystals cooled under bias electric field applied along $[001{\mathrm{]}}_{\mathrm{pc}}$ and then zero-field heated to the vicinity of the so-called depoling temperature ${T}_{\mathrm{RT}}$, 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.