Magnetization dynamics and spin pumping in Heusler compound Co2FeSi interfaced with MoS2

Abstract

We present a detailed investigation of spin pumping from full Heusler compound Co2FeSi (CFS) to single-layer two-dimensional (2D) transition metal dichalcogenide (TMD) MoS2 (molybdenum disulfide) excited by ferromagnetic resonance. Microwave-induced spin pumping has been identified by a significant enhancement of Gilbert damping in Si/SiO2/MoS2/CFS heterostructures as compared to bare Si/SiO2/CFS samples. The CFS thickness dependent spin mixing conductance indicates an efficient spin transparent interface of MoS2/CFS. In addition, the spin-to-charge conversion process has been quantified using inverse spin Hall effect (ISHE) measurements. In ISHE measurements, a highly symmetric Lorentzian DC voltage signal in Si/SiO2/MoS2/CFS heterostructures is observed in comparison with a highly asymmetric signal in bare Si/SiO2/CFS samples, establishing a clear sign of FMR induced spin pumping. The results in this work are expected to aid in the understanding of the spin angular momentum transfer phenomenon at the interface of the 2D TMDs/ferromagnet bilayer system.