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arXiv · 1806.08060

Reconstructing Entanglement Hamiltonian via Entanglement Eigenstates

W. Zhu·Zhoushen Huang·Yin-chen He
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Abstract

The entanglement Hamiltonian $H_E$, defined through the reduced density matrix of a subsystem $ρ_A=\exp(-H_E)$, is an important concept in understanding the nature of quantum entanglement in many-body systems and quantum field theories. In this work, we explore a numerical scheme which explicitly reconstructs the entanglement Hamiltonian using one entangled mode (i.e., an eigenstate) of $ρ_A$. We demonstrate and benchmark this scheme on quantum spin lattice models. The resulting $H_E$ bears a form similar to a physical Hamiltonian with spatially varying couplings, which allows us to make quantitative comparison with perturbation theory and conformal field theory.

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W. Zhu, Zhoushen Huang, Yin-chen He. 2018-06-21. Reconstructing Entanglement Hamiltonian via Entanglement Eigenstates. https://doi.org/10.1103/physrevb.99.235109

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