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arXiv · 1909.07284

Effect of Ba and Zr co-substitution on dielectric and magnetoelectric properties of BiFeO3 multiferroics

Abstract

We report the effect of Ba and Zr co-substitution on structural, dielectric, magnetic and magnetoelectric properties of BiFeO3 multiferroics. Polycrystalline nanoceramic samples of Bi1- xBaxFe1-yZryO3 have been synthesized by auto-combustion method. Rietveld refinement result of X-ray diffraction data indicate a contraction of unit cell volume with increase in x and y. Field emission scanning electron micrographs show densely populated grains without any voids or defects with well-defined grain boundary and decrease in grain size with increasing x and y. The result of dielectric measurement display anomalies, which are amplified and the temperature at which dielectric anomalies observed decreases with increasing composition. A cross-over from anti-ferromagnetism to weak ferromagnetism has been observed at x = y = 0.1 with enhanced magnetization as compared to pure BiFeO3. Ferroelectric properties of the sample have been studied using PE loop measurement. Magneto-dielectric and magneto impedance spectroscopy reveal the existence of intrinsic magneto-electric coupling at room temperature.

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Satya Tripathy, Dhiren Pradhan, S Sen, BG Mishra, R Palai, JF Scott, R. S. Katiyar, Dillip pradhan. 2019-09-09. Effect of Ba and Zr co-substitution on dielectric and magnetoelectric properties of BiFeO3 multiferroics. https://arxiv.org/abs/1909.07284

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