Evolution of pairwise entanglement in a coupled n-body system (6 pages)

  title={Evolution of pairwise entanglement in a coupled n-body system (6 pages)},
  author={Carlos Pineda and Thomas H. Seligman},
  journal={Physical Review A},
We study the exact evolution of two noninteracting qubits, initially in a Bell state, in the presence of an environment, modeled by a kicked Ising spin chain. Dynamics of this model range from integrable to chaotic and we can handle numerics for a large number of qubits. We find that the entanglement (as measured by concurrence) of the two qubits has a close relation to the purity of the pair, and closely follows an analytic relation derived for Werner states. As a collateral result we find… 

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