Anomalous freezing of dielectric polarons near magnetic ordering in multiferroic La<inf>0.5</inf>Bi<inf>0.5</inf>FeO<inf>3</inf>

A single-phase multiferroic (MF) La0.5Bi0.5FeO3 (LBFO) ceramic sample was prepared by the conventional solid-state reaction method. The crystallographic phase formation and morphological studies were carried out using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The temperature-dependent magnetization exhibits weak ferromagnetic ordering near TC = 220 K. Complex dielectric and impedance properties of LBFO as a function of temperature and frequency were performed to understand the correlation between magnetic and dielectric properties. The analysis of electrical modulus spectrum reveals that the magnetic ordering imposes a change in the activation energy of dielectric polarons. The thermal fluctuations of magnetic moments activate the freezing of dielectric polarons with enhancement in temperature.