Spin-Orbit Torque in noncentrosymmetric ferromagnetic Weyl semimetals

The unique topological effect and symmetry breaking of rare earth Weyl semimetals present substantial potential in spintronics applications. A particular example of such a material is PrAlGe. PrAlGe is a noncentrosymmetric, ferromagnetic Weyl Semimetal that breaks both time-reversal and inversion symmetry. The inversion symmetry breaking allows for the Weyl nodes to be stabilized and also allows direct control of magnetization order via spin-orbit torque. By utilizing density function theory and ab initio linear response calculations, we calculate the spin-orbit torque effect which can also be enhanced near the Weyl points. In addition, the C_4 rotational symmetry restricts the symmetry-allowed form of spin-orbit torque in terms of vector spherical harmonics. We discuss the resulting magnetization dynamics and its interplay with the topology in the presence of the calculated spin-orbit torques.