Optimal entanglement witnesses for qubits and qutrits

Reinhold Bertlmann, Katharina Durstberger, Beatrix Hiesmayr, Philipp Krammer

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We study the connection between the Hilbert-Schmidt measure of entanglement (that is the minimal distance of an entangled state to the set of separable states) and entanglement witness in terms of a generalized Bell inequality which distinguishes between entangled and separable states. A method for checking the nearest separable state to a given entangled one is presented. We illustrate the general results by considering isotropic states, in particular two-qubit and two-qutrit states-and their generalizations to arbitrary dimensions-where we calculate the optimal entanglement witnesses explicitly. Π2005 The American Physical Society.
Original languageEnglish
Article number052331
Number of pages9
JournalPhysical Review A
Issue number5
Publication statusPublished - 2005

Austrian Fields of Science 2012

  • 103036 Theoretical physics

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