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arXiv · 2001.01671

Entanglement spreading and quasiparticle picture beyond the pair structure

Alvise Bastianello·Mario Collura
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Abstract

The quasi-particle picture is a powerful tool to understand the entanglement spreading in many-body quantum systems after a quench. As an input, the structure of the excitations' pattern of the initial state must be provided, the common choice being pairwise-created excitations. However, several cases exile this simple assumption. In this work, we investigate weakly-interacting to free quenches in one dimension. This results in a far richer excitations' pattern where multiplets with a larger number of particles are excited. We generalize the quasi-particle ansatz to such a wide class of initial states, providing a small-coupling expansion of the Renyi entropies. Our results are in perfect agreement with iTEBD numerical simulations.

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BibTeXRIS

Alvise Bastianello, Mario Collura. 2020-01-06. Entanglement spreading and quasiparticle picture beyond the pair structure. https://doi.org/10.21468/scipostphys.8.3.045

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