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arXiv · 2210.07406

Symmetry-Resolved Entanglement of $C_2$-symmetric Topological Insulators

K. Monkman·J. Sirker
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Abstract

For a many-body system of arbitrary dimension, we consider fermionic ground states of non-interacting Hamiltonians invariant under a $C_2$ cyclic group. The absolute difference $\Delta$ between the number of occupied symmetric and anti-symmetric single-particle states is an adiabatic invariant. We prove lower bounds on the configurational and the number entropy based on this invariant. In band insulators, the topological invariant $\Delta$ and the entropy bounds can be directly determined from high symmetry points in the Brillouin zone.

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K. Monkman, J. Sirker. 2022-10-13. Symmetry-Resolved Entanglement of $C_2$-symmetric Topological Insulators. https://doi.org/10.1103/physrevb.107.125108

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