Ferroelectric BaTiO3 single crystal under superstrong electric fields up to 55 MV/m: A comparative experimental and theoretical study

We investigated the effect of huge electric field up to E=55 MV/m on tetragonal ferroelectric phase of BaTiO3 single crystal. Both lattice parameters and the dielectric susceptibility along the polar axis were determined. The induced polarization shows a continuous increase up to 20% of the spontaneous polarization. The longitudinal d33 and transverse d31 piezoelectric coefficients were also determined. The experimental data are described by a phenomenological approach. Interestingly, an intermediate critical electric field value of E∼25 MV/m was evidenced suggesting that the physics below and above this value are different.