Spin pumping and inverse spin Hall effect in magnetron-sputtered large area MoS2/Co40Fe40B20 bilayers

Abstract

Transition metal dichalcogenides (TMDs) are novel class of quantum materials which show potentials for optoelectronics, valleytronics, opto-valleytronics etc. TMDs are also found to exhibit high spin orbit coupling and therefore, they have been extensively studied for spin to charge conversion or spin pumping phenomena. The robustness of MoS2 and its high availability in nature as molybdenite, have made it a suitable candidate for device applications. Among all the methods designed to fabricate large area TMDs on industrially compatible substrates, the sputtering technique offers advantage to prepare large area films. Here we report the observation of spin to charge conversion in large area magnetron-sputtered MoS2 by inverse spin Hall effect (ISHE) via microwave driven ferromagnetic resonance spectroscopy. In the continuous MoS2/CoFeB thin films, angle dependent measurements of ISHE have been performed to identify various galvanometric rectification effects. The spin diffusion length, real part of spin mixing conductance and the electromotive force (emf) arising due to inverse spin Hall effect are found to be 7.83 ± 0.57 nm, (1.43 ± 0.019) × 1019 m−2 and 4.38 ± 0.12 μV, respectively. These results show that the MoS2 films exhibit high spin orbit coupling for spin to charge conversion physics and their relevance in SOT based applications.