Effects of pressure on the dielectric properties of SrTi18O3 and SrTi16O3 single crystals

A systematic research of the effects of pressure on the ferroelectricity of (SrTiO3)-O-18 and the quantum paraelectricity of (SrTiO3)-O-16 has been performed. The effects of pressure manifest themselves in the following ways: (i) suppressing T-c for (SrTiO3)-O-18; (ii) depressing dielectric pennittivity epsilon(r) for both (SrTiO3)-O-16 and (SrTiO3)-O-18; and (iii) extending the quantum paraelectric range to a higher temperature. These results can be understood in terms of a nonlinear shell mode.