English

Entanglement negativity after a local quantum quench in conformal field theories

Statistical Mechanics 2015-08-12 v2 Strongly Correlated Electrons High Energy Physics - Theory Quantum Physics

Abstract

We study the time evolution of the entanglement negativity after a local quantum quench in (1+1)-dimensional conformal field theories (CFTs), which we introduce by suddenly joining two initially decoupled CFTs at their endpoints. We calculate the negativity evolution for both adjacent intervals and disjoint intervals explicitly. For two adjacent intervals, the entanglement negativity grows logarithmically in time right after the quench. After developing a plateau-like feature, the entanglement negativity drops to the ground-state value. For the case of two spatially separated intervals, a light-cone behavior is observed in the negativity evolution; in addition, a long-range entanglement, which is independent of the distance between two intervals, can be created. Our results agree with the heuristic picture that quasiparticles, which carry entanglement, are emitted from the joining point and propagate freely through the system. Our analytical results are confirmed by numerical calculations based on a critical harmonic chain.

Keywords

Cite

@article{arxiv.1501.00568,
  title  = {Entanglement negativity after a local quantum quench in conformal field theories},
  author = {Xueda Wen and Po-Yao Chang and Shinsei Ryu},
  journal= {arXiv preprint arXiv:1501.00568},
  year   = {2015}
}

Comments

18 pages, 10 figures; Discussions and references are added