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Dynamics of Entanglement in One-Dimensional Spin Systems

L. Amico·A. Osterloh·F. Plastina·R. Fazio·G. M. Palma
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Abstract

We study the dynamics of quantum correlations in a class of exactly solvable Ising-type models. We analyze in particular the time evolution of initial Bell states created in a fully polarized background and on the ground state. We find that the pairwise entanglement propagates with a velocity proportional to the reduced interaction for all the four Bell states. Singlet-like states are favored during the propagation, in the sense that triplet-like states change their character during the propagation under certain circumstances. Characteristic for the anisotropic models is the instantaneous creation of pairwise entanglement from a fully polarized state; furthermore, the propagation of pairwise entanglement is suppressed in favor of a creation of different types of entanglement. The ``entanglement wave'' evolving from a Bell state on the ground state turns out to be very localized in space-time. Further support to a recently formulated conjecture on entanglement sharing is given.

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L. Amico, A. Osterloh, F. Plastina, R. Fazio, G. M. Palma. 2003-07-07. Dynamics of Entanglement in One-Dimensional Spin Systems. https://doi.org/10.1103/physreva.69.022304

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