Epitaxial growth and orientation-dependent anomalous Hall effect of noncollinear antiferromagnetic Mn3Ni0.35Cu0.65N films

We report the growth of noncollinear antiferromagnetic (AFM) Mn 3Ni 0.35Cu 0.65N films and the orientation-dependent anomalous Hall effect (AHE) of (001) and (111) films due to the nonzero Berry curvature. We found that post-annealing at 500  °C can significantly improve the AHE signals, though using the appropriate post-annealing conditions is important. The AHE and magnetization loops show sharp flipping at the coercive field in (111) films, while (001) films are hard to saturate by a magnetic field. The anomalous Hall conductivity of (111) films is an order of magnitude larger than that of (001) films. The present results provide not only a better understanding of the AHE in Mn 3 XN systems but also further opportunities to study the unique phenomena related to noncollinear AFM.