Ground-State Degeneracy of Correlated Insulators with Edges

Abstract

Using the topological flux insertion procedure, the ground-state degeneracy of an insulator on a periodic lattice with filling factor $\nu =p/q$ was found to be at least $q$-fold. Applying the same argument in a lattice with edges, we show that the degeneracy is modified by the additional edge density $ν_{\mysw{E}}$ associated with the open boundaries. In particular, we demonstrate that these edge corrections may even make an insulator with integer bulk filling degenerate.

arXiv comment4 pages, REVTeX 4

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Cited by in corpus (2)

• Entanglement entropy of two disjoint blocks in XY chains
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