Analytical comparison of magnetic and electrical properties using modified Landau theory in bismuth ferrite: Effect of milling

•Authors have synthesised BFO using SSR and mechano-chemical activation technique.•Asymmetry in magnetic hysteresis loops has been checked through Landau theory.•The deviation from Landau theory has been attributed to magneto-electric coupling.•A comparative analysis of magnetic and electrical properties has been done.•A relation between magnetic and electric polarization has been established.

In this study, authors have synthesized bismuth ferrite using (i) solid state route and (ii) mechano-chemical activation technique. The structural studies reveal the formation of bismuth ferrite of A3−δB5O12A3−δB5O12 type by mechanochemical activation technique and of ABO3 type by conventional solid state route. In addition to the detailed studies on magnetic and electrical properties of both the samples, a comparative analysis has been done using Landau and Berry phase theory. Through this, an effort has been made to establish a relationship between magnetism and electrical polarization vis a vis magneto-electric coupling in these samples.