Non-Linear Properties of BaTiO3 above T-C

Although numerous papers on physical properties of the BaTiO3 crystal can be found in literature, there is a lack of tentative studies of its properties in temperature range close to but above T-C. That is why investigations of temperature dependence of the dielectric properties, electrostrictive strain and thermal expansion have been undertaken. Results obtained point to non-linear behaviour of all these properties even tens degrees above TC. Especially the non-linear thermal expansion, first time measured in detail for BaTiO3 above TC, implies the existence of micro/nano-polar regions whose temperature stability and sizes are responsible for temperature hysteresis above T-C.