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arXiv · 2307.01987

Tetrahedron genuine entanglement measure of four-qubit systems

Meng-Li Guo·Zhi-Xiang Jin·Bo Li·Shao-Ming Fei
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Abstract

Quantifying genuine entanglement is a key task in quantum information theory. We study the quantification of genuine multipartite entanglement for four-qubit systems. Based on the concurrence of nine different classes of four-qubit states, with each class being closed under stochastic local operation and classical communication, we construct a concurrence tetrahedron. Proper genuine four-qubit entanglement measure is presented by using the volume of the concurrence tetrahedron. For non genuine entangled pure states, the four-qubit entanglement measure classifies the bi-separable entanglement. We show that the concurrence tetrahedron based measure of genuine four-qubit entanglement is not equivalent to the genuine four-partite entanglement concurrence. We illustrate the advantages of the concurrence tetrahedron by detailed examples.

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Meng-Li Guo, Zhi-Xiang Jin, Bo Li, Shao-Ming Fei. 2023-07-05. Tetrahedron genuine entanglement measure of four-qubit systems. https://doi.org/10.1088/1751-8121/ace409

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