Entanglement swapping in presence of dephasing
نویسندگان
چکیده
Entanglement which originates from a pair of non-interacting qubits by means of entanglement swapping is discussed when dephasing mechanisms are present. Then, the exact reduced dynamics can be evaluated for two pairs of independent qubits which each are coupled to their own bosonic environment. Each of two pairs of qubits is initially maximally entangled. The conditions for the entanglement survival at asymptotic long times in terms of environment spectral properties are elaborated. It is shown that these conditions hold true also for the inter–pair entanglement stemming. Entanglement swapping can effectively been controlled by a proper choice of initial state of the finite environment. B
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