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Decoherence of entangled kaons and its connection to entanglement measures

Reinhold A. Bertlmann·Katharina Durstberger·Beatrix C. Hiesmayr
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Abstract

We study the time evolution of the entangled kaon system by considering the Liouville - von Neumann equation with an additional term which allows for decoherence. We choose as generators of decoherence the projectors to the 2-particle eigenstates of the Hamiltonian. Then we compare this model with the data of the CPLEAR experiment and find in this way an upper bound on the strength $λ$ of the decoherence. We also relate $λ$ to an effective decoherence parameter $ζ$ considered previously in literature. Finally we discuss our model in the light of different measures of entanglement, i.e. the von Neumann entropy $S$, the entanglement of formation $E$ and the concurrence $C$, and we relate the decoherence parameter $ζ$ to the loss of entanglement: $1 - E$.

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Reinhold A. Bertlmann, Katharina Durstberger, Beatrix C. Hiesmayr. 2003-05-28. Decoherence of entangled kaons and its connection to entanglement measures. https://doi.org/10.1103/physreva.68.012111

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