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Recently discovered magnetic Weyl semimetals (MWSM), with enhanced Berry curvature stemming from the topology of their electronic band structure, have gained much interest for spintronics applications. In this category, Co2MnGa, a room temperature ferromagnetic Heusler alloy, has garnered special interest as a promising material for topologically driven spintronic applications. However, until now, the structural-order dependence of spin current generation efficiency through the spin Hall effect has not been fully explored in this material. In this paper, we study the evolution of magnetic and transport properties of Co2MnGa thin films from the chemically disordered B2 to ordered L21 phase. We also report on the change in spin generation efficiency across these different phases, using heterostructures of Co2MnGa and ferrimagnet CoxTb1−x with perpendicular magnetic anisotropy. We measured large spin Hall angles in both the B2 and L21 phases, and within our experimental limits, we did not observe the advantage brought by the MWSM ordering in generating a strong spin Hall angle over the disordered phases, which suggests more complicated mechanisms over the intrinsic, Weyl-band structure-determined spin Hall effect in these material stacks. 

The successful implementation of spin-wave devices requires efficient modulation of spin-wave propagation. Using cobalt/nickel multilayer films, we experimentally demonstrate that nanometer-wide magnetic domain walls can be applied to manipulate the phase and magnitude of coherent spin waves in a nonvolatile manner. We further show that a spin wave can, in turn, be used to change the position of magnetic domain walls by means of the spin-transfer torque effect generated from magnon spin current. This mutual interaction between spin waves and magnetic domain walls opens up the possibility of realizing all-magnon spintronic devices, in which one spin-wave signal can be used to control others by reconfiguring magnetic domain structures.