Nonlinear dielectric response in the relaxor Pb(Mg1/3Nb2/3)O3 single crystal

The temperature dependence of the third-order nonlinear dielectric constant and the time dependence of the linear dielectric constant under a step DC field in a typical relaxer, Pb(Mg1/3Nb2/3)O-3 single crystal, were measured around the temperature where the dielectric constant shows a maximum value. It was found that the nonlinear dielectric constant shows a broad peak without any indication of divergence. It was also found that the dielectric constant under the step DC field changes slowly with time. The nonlinear response of relaxer ferroelectrics was discussed.