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تسجيل مستخدم جديدDetermining the Proximity Effect Induced Magnetic Moment in Graphene by Polarised Neutron Reflectivity and X-ray Magnetic Circular Dichroism
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We report the magnitude of the induced magnetic moment in CVD-grown epitaxial and rotated-domain graphene as a result of the proximity effect in the vicinity of the ferromagnetic substrates Co and Ni, using polarised neutron reflectivity (PNR). Although rotated-domain graphene is known to interact weakly with the ferromagnetic underlayer in comparison with the epitaxial graphene, the PNR results indicate an induced magnetic moment of $sim$ 0.57 $mu_textrm{B}$/C atom at 10 K for both structures. The origin of the induced magnetic moment is found to be due to the opening of the graphenes Dirac cone as a result of the strong C $p_z-3d$ hybridisation, which was confirmed by additional PNR measurements using a non-magnetic Ni$_9$Mo$_1$ and Cu substrates. We validated our PNR fitting models using the Bayesian uncertainty analysis and corroborated the results by X-ray magnetic circular dichroism measurements.
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