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arXiv · 0711.4477

Three-tangle for mixtures of generalized GHZ and generalized W states

Christopher Eltschka·Andreas Osterloh·Jens Siewert·Armin Uhlmann
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Abstract

We give a complete solution for the three-tangle of mixed three-qubit states composed of a generalized GHZ state, a|000>+b|111>, and a generalized W state, c|001>+d|010>+f|100>. Using the methods introduced by Lohmayer et al. we provide explicit expressions for the mixed-state three-tangle and the corresponding optimal decompositions for this more general case. Moreover, as a special case we obtain a general solution for a family of states consisting of a generalized GHZ state and an orthogonal product state.

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Christopher Eltschka, Andreas Osterloh, Jens Siewert, Armin Uhlmann. 2007-11-28. Three-tangle for mixtures of generalized GHZ and generalized W states. https://doi.org/10.1088/1367-2630%2F10%2F4%2F043014

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