  We analyse the electrical response of narrow graphene nanogaps in search for
transport signatures stemming from spin-polarized edge states. We find that the
electrical transport across graphene nanogaps having perfectly defined zigzag
edges does not carry any spin-related signature. We also analyse the magnetic
and electrical properties of nanogaps whose electrodes have wedges that
possibly occur in the currently fabricated nanogaps. These wedges can host spin
polarized wedge low-energy states due to the bipartite nature of the graphene
lattice. We find that these spin-polarized low-energy modes give rise to
low-voltage signatures in the differential conductance and to distinctive
features in the stability diagrams. These are caused by fully spin-polarized
currents.
