Electric-Field-Enhanced Bulk Perpendicular Magnetic Anisotropy in GdFe/Pb(Mg_1/3Nb_2/3)_0.7Ti_0.3O₃ Multiferroic Heterostructure

Perpendicular magnetic anisotropy is important for increasing the information storage density in the perpendicular magnetic recording media, and for rare-earth–transition-metal alloys with bulk perpendicular magnetic anisotropy that generate great research interest due to their abundant interesting phenomena, such as fast domain wall motion and skyrmion. Here, we deposit amorphous GdFe ferrimagnetic films on Pb(Mg1/3Nb2/3)0.7Ti0.3O3 ferroelectric substrate and investigate the effect of electric-field-induced piezostrain on its bulk perpendicular magnetic anisotropy. The anomalous Hall effect and polar Kerr image measurements suggest an enhanced bulk perpendicular magnetic anisotropy by electric field, which originates from a positive magnetoelastic anisotropy due to the positive magnetostriction coefficient of the GdFe film and the electric-field-induced tensile strain along the z axis in Pb(Mg1/3Nb2/3)0.7Ti0.3O3 ferroelectric substrate. Our results enrich the electrical control of perpendicular magnetic anisotropy and are useful for designing spintronic devices based on perpendicular magnetic anisotropy.