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

  title={Ground-state degeneracy for Abelian anyons in the presence of gapped boundaries},
  author={Anton Kapustin},
  journal={Physical Review B},
  • A. Kapustin
  • Published 18 June 2013
  • Physics
  • Physical Review B
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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