Hierarchical micro-/nanoscale domain structure in MC phase of (1−x)Pb(Mg1∕3Nb2∕3)O3–xPbTiO3 single crystal

A hierarchical micro-/nanoscale domain structure is revealed in $M_C$ phase of $(1-x)\mathrm{Pb}\left({\mathrm{Mg}}_{1∕3}{\mathrm{Nb}}_{2∕3}\right){\mathrm{O}}_3–x\mathrm{Pb}\mathrm{Ti}{\mathrm{O}}_3$ single crystal near the morphotropic phase boundary by combination of analytical electron microscopy and polarized light microscopy. The hierarchical domain structure is a self-assembling of nanodomains with tetragonal structure, submicrodomains appearing as monoclinic, and microdomains exhibiting the same monoclinic state due to an average effect. The outstanding piezoelectric properties may result from the cooperative response of the hierarchical micro-/nanoscale domain structure.