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arXiv · 2410.10090

Sudden change in entanglement Hamiltonian: Phase diagram of an Ising entanglement Hamiltonian

Zhe Wang·Siyi Yang·Bin-Bin Mao·Meng Cheng·Zheng Yan
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Abstract

The form of the entanglement Hamiltonian varies with the parameters of the original system. Whether there is a singularity is the key problem for demonstrating/negating the universality of the relation between the entanglement spectrum and edge energy spectrum. We carefully study the phase diagram of a 1D Ising entanglement Hamiltonian as an example to clarify the long-standing controversy of the general relation between the entanglement Hamiltonian and original Hamiltonian. Interestingly, even if the singularities indeed exist, the Li-Haldane-Poilblanc conjecture, i.e., the general relation between the entanglement spectrum and edge energy spectrum, seemingly still holds.

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Zhe Wang, Siyi Yang, Bin-Bin Mao, Meng Cheng, Zheng Yan. 2024-10-14. Sudden change in entanglement Hamiltonian: Phase diagram of an Ising entanglement Hamiltonian. https://arxiv.org/abs/2410.10090

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