逆ペロブスカイト型遷移金属窒化物薄膜の電流磁気効果

摘要

γ'-Fe_4N, a ferromagnetic antiperovskite-type transition metal nitride, has attracted much attention for its novel magnetotransport properties, originated from electron orbital hybridization between Fe and N atoms, and for its potential applications in spintronics devices as a highly spin-polarized material. In this article, anomalous behaviors are reported for the negative anisotropic magnetoresistance (AMR) and anomalous Hall effects of pseudo single crystal Fe_4N thin films. The origin of these anomalous behaviors, observed below 50 K, is discussed through an analysis based on electron scattering theory, which takes into account the spin-orbit interaction and tetragonal crystal field effects. Perpendicular magnetic anisotropy and magneto-transport properties are also reported for the pseudo single crystal thin films of ε-Mn_4N，a ferrimagnetic antiperovskite-type nitride. Sign changes are observed for AMR and anomalous Hall effects with lowering measurement temperature. The magnitudes of AMR ratio and anomalous Hall conductivity of the Mn_4N films significantly change below 100 K, similarly to the anomalous behaviors of those of the Fe_4N films.