Title: Enhancement of spin current to charge current conversion in Ferromagnet/Graphene interface

Abstract: The use of graphene in spintronic devices depend, on its ability to convert a spin current into an electric charge current. We have systematically investigated the spin pumping induced spin-to-charge current conversion at the Graphene/FM interface and the effect of interface modification through high spin orbit coupling (SOC) material (Pt) as an interlayer (IL) of varying thicknesses by using broadband FMR spectroscopy. The spin mixing conductance was enhanced from $1.66 \times 10^{18}$ m$^{-2}$ to $2.72 \times 10^{18}$ m$^{-2}$ where as the spin current density was enhanced from 0.135$\pm $0.003 to 0.242$\pm$0.004 MA/m$^{2}$ at the Graphene/FM interface due to the interface modification using high SOC material Pt as an interlayer. We observe the value of spin current to charge current conversion efficiency $\approx 0.292\times10^{-3}$ nm for the Graphene/FM interface. These findings support the idea that Graphene in contact with high SOC material (Pt) be a potential candidate for spintronic applications, specifically for spin-torque-based memory applications.