Entanglement of Purification in Many Body Systems and Symmetry Breaking
arXiv:1902.02369 · doi:10.1103/PhysRevLett.122.201601
Abstract
We study the entanglement of purification (EoP), a measure of total correlation between two subsystems and , for free scalar field theory on a lattice and the transverse-field Ising model by numerical methods. In both of these models, we find that the EoP becomes a non-monotonic function of the distance between and when the total number of lattice sites is small. When it is large, the EoP becomes monotonic and shows a plateau-like behavior. Moreover, we show that the original reflection symmetry which exchanges and can get broken in optimally purified systems. In the Ising model, we find this symmetry breaking in the ferromagnetic phase. We provide an interpretation of our results in terms of the interplay between classical and quantum correlations.
12 pages, 18 figures