New material platforms for antiferromagnetic spintronics (Conference Presentation)

Abstract

Antiferromagnetic (AFM) spintronics is an emerging field of research, which exploits the Neel vector to control spin- and orbital-dependent transport properties. This talk will address two approaches, involving new material platforms, which can be exploited in AFM spintronics. The first approach comprises the subfield of AFM spintronics known as topological AFM spintronics, where the Neel vector is used to electrically manipulate the symmetry-related topological states. Based on density-functional theory calculations, we demonstrate that room temperature AFM metal MnPd2 allows the electrical control of the Dirac nodal line by the Neel spin-orbit torque. The reorientation of the Neel vector leads to switching between the symmetry-protected degenerate state and the gapped state associated with the dispersive Dirac nodal line at the Fermi energy. The calculated spin Hall conductivity strongly depends on the Neel vector orientation and thus can be used to experimentally detect the predicted effect. The second approach involves Neel vector switching in non-collinear antiferromagnets ANMn3 (A = Ga, Ni, Zn, etc.) with an antiperovskite structure. These compounds are characterized by the competing non-collinear AFM Γ5g and Γ4g phases. We demonstrate from first-principles that by stoichiometry engineering ANMn3 can be tuned close to the critical transition point between the Γ5g and Γ4g phases, at which the Neel vector switching can be achieved by strain or spin-transfer torque. The switching can be detected through the anomalous Hall effect being zero or finite for the Γ5g and Γ4g phases, respectively, due to the symmetry of the Berry curvature. Our results broaden the scope of materials and approaches, which can be exploited in AFM spintronics.