NMR and the spherical random bond–random field model of relaxor ferroelectrics Original Research Article

To determine the nature of the relaxor state and, in particular, to discriminate between a ferroelectric state broken up into nanodomains under the constraint of quenched random fields and a glassy state we have measured the temperature dependences of the nonlinear dielectric susceptibility in zero field as well as the temperature dependence of the local polarization distribution function and the Edwards–Anderson order parameter in PMN single crystal via 93Nb NMR. The experimental results can be quantitatively described by the newly proposed Spherical Random Bond–Random Field model of relaxor ferroelectrics.