Electrostrictive properties of nanosize PbTiO3

摘要

Properties of nanosize PbTiO3 are discussed from thenstandpoint of the effects of crystallite size on electrostrictivenbehavior. Experimental results based on crystallite size-dependentnprimary and secondary order parameters (spontaneous polarization andnstrain) show that the critical crystallite size (CCS) for thenstabilization of the cubic paraelectric phase at 298 K is around 15 nm.nThe CCS inversely scales with the cubic-tetragonal transitionntemperature (Ttr). Electrostrictive coefficients exhibit annorder of magnitude increase at 28 nm, which is attributed to thenanharmonicity of the perovskite lattice. First order calculationsnindicate that the increase in the electrostrictive coefficients offsetsnthe decrease in spontaneous polarization and results in an increase innpiezoelectric moduli suggesting that piezoelectric activity could, innprinciple, be observed in the nanosize regime