Graphene nanoribbons are known to have edge states which are dispersionless zero energy modes along both edges. Edge states in these ribbons are able to travel hundreds of micrometers without scattering, making them excellent electronic conductors. Our group first measured these edge states in 2010 (Baringhaus et al. 2014, Nature, doi:10.1038/nature12952, arXiv:1301.5354), showing that they have conductance quantized in units of e2/h.

In 2022 we showed that the edge state survives patterning and involve a zero-energy quasiparticle that presents no Hall effect and act like half an electron and half a hole. (Prudkovskiy et al. 2022, Nature Communiciations, doi:10.1038/s41467-022-34369-4). The properties of this quasiparticle are not well understood and are an active area of research.