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The Bound of Entanglement of Superpositions with More Than Two Components

Yang Xiang·Shi-Jie Xiong·Fang-Yu Hong
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Abstract

A bipartite quantum state (for two systems in any dimensions) can be decomposed as a superposition of many components. For a superposition of more than two components we prove that there is a bound of the entanglement of the superposition state which can be expressed according to entanglements of its component states. Especially, if the component states are mutually bi-orthogonal, the entanglement of the superposition state can be exactly given in terms of the entanglements of the states being superposed.

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Yang Xiang, Shi-Jie Xiong, Fang-Yu Hong. 2008-02-10. The Bound of Entanglement of Superpositions with More Than Two Components. https://doi.org/10.1140/epjd%2Fe2008-00022-6

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