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arXiv · 2206.09199

Mimicking quantum correlation of a long-range Hamiltonian by finite-range interactions

Leela Ganesh Chandra Lakkaraju·Srijon Ghosh·Debasis Sadhukan·Aditi Sen De
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Abstract

The quantum long-range extended Ising model possesses several striking features that cannot be observed in the corresponding short-range model. We report that the pattern obtained from the entanglement between any two arbitrary sites of the long-range model can be mimicked by the model having a finite range of interactions provided the interaction strength is moderate. On the other hand, we illustrate that when the interactions are strong, the entanglement distribution in the long-range model does not match the class of a model with a few interactions. We also show that the monogamy score of entanglement is in good agreement with the behavior of pairwise entanglement. Specifically, it saturates when the entanglement in the finite-range Hamiltonian behaves similarly to the long-range model, while it decays algebraically otherwise.

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Leela Ganesh Chandra Lakkaraju, Srijon Ghosh, Debasis Sadhukan, Aditi Sen De. 2022-06-18. Mimicking quantum correlation of a long-range Hamiltonian by finite-range interactions. https://doi.org/10.1103/physreva.106.052425

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