Spintronics in Half-Passivated Graphene
Abstract
In this thesis, I propose a practical way to stabilize half passivated graphene (graphone). I show that the dipole moments induced by a hexagonal-boron nitride (h-BN) substrate on graphene stabilize the hydrogen atoms on one sublattice of the graphene layer and suppress the migration of the adsorbed hydrogen atoms. I also present the substrate effect of h-BN that reduces distortion induced by fluorination of graphene and stabilizes half-passivated graphene in a single sublattice. Then using spin-polarized density functional calculations I investigate magnetic properties of graphone. I show the system has different magnetic order which can be described by either super-exchange or double exchange mechanisms depending on the type of add atom. The hybridization of graphene changes from sp^2- to sp^3- type hybridization due to the buckling induced by passivation. The change in hybridization together with add-atom orbitals induces a fairly large spin orbit coupling (SOC). Based upon first principle spin-polarized density of states calculations, I show that the graphone obtained in different graphene/h-BN heterostructures exhibits a half metallic state. I propose to use this exotic material for spin valve systems and other spintronics devices.
Citation
Hemmatiyan, Shayan (2016). Spintronics in Half-Passivated Graphene. Doctoral dissertation, Texas A & M University. Available electronically from https : / /hdl .handle .net /1969 .1 /159036.