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

TL;DR

This study demonstrates enhanced spin current to charge current conversion at Graphene/FM interfaces through interface modification with high spin orbit coupling material Pt, indicating potential for advanced spintronic devices.

Contribution

It provides a systematic investigation of interface modifications with Pt to improve spin-to-charge conversion efficiency in Graphene/FM interfaces.

Findings

Spin mixing conductance increased with Pt interlayer.

Spin current density was significantly enhanced.

Conversion efficiency suggests potential for spintronic applications.

Abstract

The use of graphene in spintronic devices is contingent on its ability to convert a spin current into a 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 is enhanced from $1.66 \times 10^{18}$ m$^{-2}$ to $2.72 \times 10^{18}$ m$^{-2}$ whereas the spin current density is 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. The spin current to charge current conversion efficiency turns out to be $\approx 0.003$ nm for the Graphene/FM interface. These findings support the idea that Graphene in combination with high SOC material (Pt) could be a potential candidate for spintronic applications, specifically for spin-torque-based memory applications.