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arXiv:2101.00801 · Journal of Mathematical Physics

An index for two-dimensional SPT states

Nikita Sopenko

Published Nov 1, 2021• 13 citations
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Abstract

We define an index for 2D G-invariant invertible states of bosonic lattice systems in the thermodynamic limit for a finite symmetry group G with a unitary action. We show that this index is an invariant of the symmetry protected phase.
DOI
10.1063/5.0055704

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