Evidence of half-metallicity and multiferroic characters of tetragonal BaTi0.875Fe0.125O3: DFT-based calculation

Abstract

In this paper, we discuss significant results obtained in both electronic and magnetic properties when the insulator, non magnetic but ferroelectric tetragonal oxyde perovskite BaTiO3 is modified by the substitution of an iron atom among 8 Ti atoms so that Fe content x = 0.125; our new material is BaTi0.875Fe0.125O3, hereafter referred to as TBTFO. Explicetely, we will use density functional theory (DFT) to show that tetragonal BaTi0.875Fe0.125O3 acquires a half-metal ferromagnetic character, with a net integer magnetic moment of 4.0 μB, along with an intrinsic polarization although reduced by 39 % when compared to the host material BaTiO3. This is an important result since the new material is presenting both ferroelectricity and ferromagnetism, i.e. multiferroelectricity. So it belongs to a very limted class of materials called multiferroics and giving up to a precious material suitable for opening up the application field of spintronics.