Strain-induced magnetoelectric coupling in BaTiO3/Fe3O4 core/shell nanoparticles

Abstract

We report a strain-induced magnetoelectric coupling in BaTiO3/Fe3O4 ferroelectric core/ferrimagnetic shell nanoparticles. The temperature-dependent magnetoresistance and magnetization clearly show several jumps near the structural phase transition temperatures of BaTiO3. Below the Verwey transition temperature of Fe3O4, i.e., at 20 K, the dielectric constant of BaTiO3/Fe3O4 decreases continuously upon application of an external magnetic field, and the observed magnetodielectric curve does not follow the square of the magnetization. We discuss the effect of strain on the electric field-dependent magnetic anisotropy near the core/shell interface.