Negativity Hamiltonian: An Operator Characterization of Mixed-State Entanglement

In the context of ground states of quantum many-body systems, the locality of entanglement between connected regions of space is directly tied to the locality of the corresponding entanglement Hamiltonian: the latter is dominated by local, few-body terms. In this work, we introduce the negativity Ha...

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Bibliographic Details
Main Authors: Calabrese, P. (Author), Dalmonte, M. (Author), Murciano, S. (Author), Vitale, V. (Author)
Format: Article
Language:English
Published: American Physical Society 2022
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Online Access:View Fulltext in Publisher
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Summary:In the context of ground states of quantum many-body systems, the locality of entanglement between connected regions of space is directly tied to the locality of the corresponding entanglement Hamiltonian: the latter is dominated by local, few-body terms. In this work, we introduce the negativity Hamiltonian as the (non-Hermitian) effective Hamiltonian operator describing the logarithm of the partial transpose of a many-body system. This allows us to address the connection between entanglement and operator locality beyond the paradigm of bipartite pure systems. As a first step in this direction, we study the structure of the negativity Hamiltonian for fermionic conformal field theories and a free-fermion chain: in both cases, we show that the negativity Hamiltonian assumes a quasilocal functional form, that is captured by simple functional relations. © 2022 American Physical Society.
ISBN:00319007 (ISSN)
DOI:10.1103/PhysRevLett.128.140502