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Quantify entanglement by concurrence hierarchy

Heng Fan·Keiji Matsumoto·Hiroshi Imai
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Abstract

We define the concurrence hierarchy as d-1 independent invariants under local unitary transformations in d-level quantum system. The first one is the original concurrence defined by Wootters et al in 2-level quantum system and generalized to d-level pure quantum states case. We propose to use this concurrence hierarchy as measurement of entanglement. This measurement does not increase under local quantum operations and classical communication.

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Heng Fan, Keiji Matsumoto, Hiroshi Imai. 2002-11-11. Quantify entanglement by concurrence hierarchy. https://doi.org/10.1088/0305-4470%2F36%2F14%2F316

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