Origins of the large piezoelectric response of samarium-doped lead magnesium niobate-lead titanate ceramics.

The recent discovery of the large piezoelectric response of Pb(MgNb)O-PbTiO (PMN-PT) ceramics induced by samarium doping has provided a substantially improved functionality to the group of lead-based relaxor-ferroelectric materials. Different mechanisms have been so far proposed for the large piezoelectricity; however, the explanations are contradictory and focused on a unified description. Here, we use nonlinear harmonic piezoelectric measurements combined with multiscale structural analysis to clarify the origins of the ultrahigh piezoelectric response of samarium-doped PMN-PT.