# Ground-state degeneracy for Abelian anyons in the presence of gapped boundaries

@article{Kapustin2014GroundstateDF, title={Ground-state degeneracy for Abelian anyons in the presence of gapped boundaries}, author={Anton Kapustin}, journal={Physical Review B}, year={2014}, volume={89}, pages={125307} }

Gapped phases with long-range entanglement may admit gapped boundaries. If the boundary is gapped, the ground-state degeneracy is well defined and can be computed using methods of topological quantum field theory. We derive a general formula for the ground-state degeneracy for Abelian fractional quantum Hall phases, including the cases when connected components of the boundary are subdivided into an arbitrary number of segments, with a different boundary condition on each segment, and in the…

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