Nonlinear Dielectric Properties of the Relaxor Ferroelectric of Lead Magnoniobate - Scandoniobate

The present work reports a study on nonlinear dielectric properties of the relaxor ferroelectric of lead magnoniobate - scandoniobate (PMN-PSN) prepared in a solid solution form with a component ratio of 0.55:0.45. The results of linear dielectric properties are also provided for comparison. A combination of Scanning Electron Microscopy - Energy Dispersive Spectroscopy (SEM-EDS), X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) was employed to characterize the synthesized material. The nonlinear dielectric spectroscopy was analyzed based on higher current harmonics under an applied harmonic electric field. The obtained results indicated the existence of the so-called “superparaelectric” state within a temperature range from 306 K to 459 K, characterized by polar nanoregions embedded in a paraelectric matrix. Besides, at temperatures below 306 K, an external electric field induced a ferroelectric state, whereas a transition to a conventional paraelectric phase was observed above 459 K. The data confirmed the high sensitivity of relaxor systems to external stimuli and enabled a detailed tracing of the evolution of polar order over a wide temperature interval.