The local content of bipartite qubit correlations
نویسندگان
چکیده
One of the last open problems concerning two qubits in a pure state is to find the exact local content of their correlation, in the sense of Elitzur, Popescu, and Rohrlich (EPR2) [A. C. Elitzur, S. Popescu, and D. Rohrlich, Phys. Lett. A162, 25 (1992)]. We propose an EPR2 decomposition that allows us to prove, for a wide range of states |ψ(θ)〉=cosθ|00〉+sinθ|11〉, that their local content is pL̅ (θ)=cos2θ. We also share reflections on how to possibly extend this result to all two-qubit pure states. BRANCIARD, Cyril, GISIN, Nicolas, SCARANI, Valerio. Local content of bipartite qubit correlations. Physical Review. A, 2010, vol. 81, no. 2, p. 6 p. DOI : 10.1103/PhysRevA.81.022103
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