Journal article
Control of the local magnetic states in graphene with voltage and gating
Magnetism of graphene can be created by atomic defects, either hydrogen adsorption or single-carbon vacancy formation, owing to the unpaired π electrons around the defects. Here we explore, based on rigorous first principles calculations, the possibility of voltage manipulation of two such types of π magnetism in graphene via a scanning tunneling microscope tip.
We find a remarkably different behavior. For the hydrogen, the magnetic moment can be switched on and off with voltage-induced doping, whereas, for the carbon vacancy, the spin splitting of the π bands persists, almost independent of the extent of doping, due to the coupling between the π and the σ bonds.
Furthermore, the local atomic structures near the vacancy can be reversibly manipulated by a coordination mechanism between an intermediate tip-defect distance and a moderate tip voltage, consequently leading to the reversal of spin polarization of the π bands. Voltage control of the local magnetic states may open a new avenue for potential applications in spintronics.
Language: | English |
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Year: | 2021 |
ISSN: | 1550235x , 24699950 and 24699969 |
Types: | Journal article |
DOI: | 10.1103/PhysRevB.103.L241402 |
ORCIDs: | Brandbyge, Mads , 0000-0003-1010-3567 and 0000-0002-4530-5022 |