English

Entanglement spreading and quasiparticle picture beyond the pair structure

Statistical Mechanics 2020-03-25 v3 Strongly Correlated Electrons Quantum Physics

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.

Keywords

Cite

@article{arxiv.2001.01671,
  title  = {Entanglement spreading and quasiparticle picture beyond the pair structure},
  author = {Alvise Bastianello and Mario Collura},
  journal= {arXiv preprint arXiv:2001.01671},
  year   = {2020}
}

Comments

15 pages; 7 figures

R2 v1 2026-06-23T13:04:07.700Z