Perpendicular magnetic anisotropy of Mn4N films on MgO(001) and SrTiO3(001) substrates

Abstract

We grew Mn4N epitaxial thin films capped with Au layers on MgO(001) and SrTiO3(001) substrates by molecular beam epitaxy. Perpendicular magnetic anisotropy (PMA) was confirmed in all the samples at room temperature from the magnetization versus magnetic field curves using superconducting quantum interference device magnetometer. From the ω-2θ x-ray diffraction (XRD) and ϕ-2θχ XRD patterns, the ratios of perpendicular lattice constant c to in-plane lattice constant a, c/a, were found to be about 0.99 for all the samples. These results imply that PMA is attributed to the in-plane tensile strain in the Mn4N films.