  We study a graphene Hall probe located on top of a magnetic surface as a
detector of skyrmions, using as working principle the anomalous Hall effect
produced by the exchange interaction of the graphene electrons with the
non-coplanar magnetization of the skyrmion. We study the magnitude of the
effect as a function of the exchange interaction, skyrmion size and device
dimensions. Our calculations for multiterminal graphene nanodevices, working in
the ballistic regime, indicate that for realistic exchange interactions a
single skyrmion would give Hall voltages well within reach of the experimental
state of the art. The proposed device could act as an electrical transducer
that marks the presence of a single skyrmion in a nanoscale region, paving the
way towards the integration of skyrmion-based spintronics and graphene
electronics.
