Cluster magnetic octupole induced out-of-plane spin polarization in\n antiperovskite antiferromagnet

Abstract

Out-of-plane spin polarization {\\sigma}_z has attracted increasing interests\nof researchers recently, due to its potential in high-density and low-power\nspintronic devices. Noncollinear antiferromagnet (AFM), which has unique\n120{\\deg} triangular spin configuration, has been discovered to possess\n{\\sigma}_z. However, the physical origin of {\\sigma}_z in noncollinear AFM is\nstill not clear, and the external magnetic field-free switching of\nperpendicular magnetic layer using the corresponding {\\sigma}_z has not been\nreported yet. Here, we use the cluster magnetic octupole in antiperovskite AFM\nMn3SnN to demonstrate the generation of {\\sigma}_z. {\\sigma}_z is induced by\nthe precession of carrier spins when currents flow through the cluster magnetic\noctupole, which also relies on the direction of the cluster magnetic octupole\nin conjunction with the applied current. With the aid of {\\sigma}_z, current\ninduced spin-orbit torque (SOT) switching of adjacent perpendicular ferromagnet\nis realized without external magnetic field. Our findings present a new\nperspective to the generation of out-of-plane spin polarizations via\nnoncollinear AFM spin structure, and provide a potential path to realize\nultrafast high-density applications.\n