Direct observation of the formation of polar nanoregions in Pb(Mg1/3Nb2/3)O3 using neutron pair distribution function analysis -: art. no. 147602

Using neutron pair distribution function analysis over the temperature range from 1000 to 15 K, we demonstrate the existence of local polarization and the formation of medium-range, polar nanoregions (PNRs) with local rhombohedral order in a prototypical relaxor ferroelectric Pb(Mg1/3Nb2/3)O-3. We estimate the volume fraction of the PNRs as a function of temperature and show that this fraction steadily increases from 0% to a maximum of similar to 30% as the temperature decreases from 650 to 15 K. Below T similar to 200 K the volume fraction of the PNRs becomes significant, and PNRs freeze into the spin-glass-like state.