Size effects on the quantum paraelectric SrTiO3 nanocrystals

Nano-size effects on the dielectric properties in the quantum paraelectric SrTiO3 were studied. Nanocrystalline SrTiO3 powders were prepared by the sol-gel method, and the particle sizes were controlled by varying firing temperatures. The size were determined to be from 12 to 44 nm using Scherrer's formula. The classical paraelectric to quantum paraelectric phase transition temperatures were suggested to be increased for the smaller particle size samples. These results could be explained with the aid of transverse Ising model.