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arXiv · 0710.3425

An entanglement measure for n-qubits

D. Li·X. Li·H. Huang
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Abstract

Recently, Coffman, Kundu, and Wootters introduced the residual entanglement for three qubits to quantify the three-qubit entanglement in Phys. Rev. A 61, 052306 (2000). In Phys. Rev. A 65, 032304 (2007), we defined the residual entanglement for $n$ qubits, whose values are between 0 and 1. In this paper, we want to show that the residual entanglement for $n$ qubits is a natural measure of entanglement by demonstrating the following properties. (1). It is SL-invariant, especially LU-invariant. (2). It is an entanglement monotone. (3). It is invariant under permutations of the qubits. (4). It vanishes or is multiplicative for product states.

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D. Li, X. Li, H. Huang. 2009-01-27. An entanglement measure for n-qubits. https://doi.org/10.1063/1.3050298

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