Spin to charge and charge to spin conversion in a Dirac semimetal*

We report evidence of spin to charge and charge to spin conversion at room temperature in thin films of the archetypal three-dimensional Dirac semimetal Cd₃As₂ grown by molecular beam epitaxy. This has been detected by means of ferromagnetic driven spin pumping (SP) and spin torque ferromagnetic resonance (ST-FMR) in NiFe/Cd₃As₂ heterostructures. Analysis of the frequency and power dependence of the SP signal and of the symmetric and antisymmetric contributions to the mixing voltage in ST-FMR show that the behavior of these processes is consistent with previously reported spin to charge conversion mechanisms in heavy metals and topological insulators. Finally, we compare the efficiency of these phenomena with the one due to the inverse spin Hall effect in NiFe/Platinum bilayers.