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Information-Theoretic Measure of Genuine Multi-Qubit Entanglement

Jian-Ming Cai·Zheng-Wei Zhou·Xing-Xiang Zhou·Guang-Can Guo
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Abstract

We consider pure quantum states of N qubits and study the genuine N-qubit entanglement that is shared among all the N qubits. We introduce an information-theoretic measure of genuine N-qubit entanglement based on bipartite partitions. When N is an even number, this measure is presented in a simple formula, which depends only on the purities of the partially reduced density matrices. It can be easily computed theoretically and measured experimentally. When N is an odd number, the measure can also be obtained in principle.

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Jian-Ming Cai, Zheng-Wei Zhou, Xing-Xiang Zhou, Guang-Can Guo. 2006-09-10. Information-Theoretic Measure of Genuine Multi-Qubit Entanglement. https://doi.org/10.1103/physreva.74.042338

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