Aharonov-Bohm effect and broken valley degeneracy in graphene rings

@article{Recher2007AharonovBohmEA,
  title={Aharonov-Bohm effect and broken valley degeneracy in graphene rings},
  author={Patrik Recher and Bjorn Trauzettel and Adam Rycerz and Yaroslav M. Blanter and C. W. J. Beenakker and Alberto F. Morpurgo},
  journal={Physical Review B},
  year={2007},
  volume={76},
  pages={235404}
}
We analyze theoretically the electronic properties of Aharonov-Bohm rings made of graphene. We show that the combined effect of the ring confinement and applied magnetic flux offers a controllable way to lift the orbital degeneracy originating from the two valleys, even in the absence of intervalley scattering. The phenomenon has observable consequences on the persistent current circulating around the closed graphene ring, as well as on the ring conductance. We explicitly confirm this… 
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