Manipulation of Spin Transport in Graphene by Surface Chemical Doping

TL;DR

This study explores how surface chemical doping with gold affects spin transport in graphene, revealing complex relaxation mechanisms and demonstrating control over spin signals.

Contribution

It provides new insights into spin relaxation mechanisms in graphene and shows how surface doping can manipulate spin transport properties.

Findings

Gold doping alters the non-local spin signal in graphene.

Charged impurity scattering is not the main cause of spin relaxation.

Unexpected increases in spin lifetime suggest complex relaxation processes.

Abstract

The effects of surface chemical doping on spin transport in graphene are investigated by performing non-local measurements in ultrahigh vacuum while depositing gold adsorbates. We demonstrate manipulation of the gate-dependent non-local spin signal as a function of gold coverage. We discover that charged impurity scattering is not the dominant mechanism for spin relaxation in graphene, despite its importance for momentum scattering. Finally, unexpected enhancements of the spin lifetime illustrate the complex nature of spin relaxation in graphene.