Entanglement Signatures of Multipolar Higher Order Topological Phases

Oleg Dubinkin; Taylor L. Hughes

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arXiv · 2002.08385

Entanglement Signatures of Multipolar Higher Order Topological Phases

Oleg Dubinkin·Taylor L. Hughes

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Abstract

We propose a procedure that characterizes free-fermion or interacting multipolar higher-order topological phases via their bulk entanglement structure. To this end, we construct nested entanglement Hamiltonians by first applying an entanglement cut to the ordinary many-body ground state, and then iterating the procedure by applying further entanglement cuts to the (assumed unique) ground state of the entanglement Hamiltonian. We argue that an $n$-th order multipolar topological phase can be characterized by the features of its $n$-th order nested entanglement Hamiltonian e.g., degeneracy in the entanglement spectrum. We explicitly compute nested entanglement spectra for a set of higher-order fermionic and bosonic multipole phases and show that our method successfully identifies such phases.

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Oleg Dubinkin, Taylor L. Hughes. 2020-02-19. Entanglement Signatures of Multipolar Higher Order Topological Phases. https://arxiv.org/abs/2002.08385

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