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arXiv · 2411.11485

Quantum Coherence: A Fundamental Resource for Establishing Genuine Multipartite Correlations

Abstract

We establish the profound equivalence between measures of genuine multipartite entanglement(GME) and their corresponding coherence measures. Initially we construct two distinct classes of measures for genuine multipartite entanglement utilizing real symmetric concave functions and the convex roof technique. We then demonstrate that all coherence measures for any qudit states, defined through the convex roof approach, are identical to our two classes of GME measures of the states combined with an incoherent ancilla under a unitary incoherent operation. This relationship implies that genuine multipartite entanglement can be generated from the coherence inherent in an initial state through the unitary incoherent operations. Furthermore, we explore the interplay between coherence and other forms of genuine quantum correlations, specifically genuine multipartite steering and genuine multipartite nonlocality. In the instance of special three-qubit X-states (only nonzero elements of X-state are diagonal or antidiagonal when written in an orthonormal basis), we find that genuine multipartite steering and nonlocality are present if and only if the coherence exists in the corresponding qubit states.

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Zong Wang, Zhihua Guo, Zhihua Chen, Ming Li, Zihang Zhou, Chengjie Zhang, Shao-Ming Fei, Zhihao Ma. 2024-11-18. Quantum Coherence: A Fundamental Resource for Establishing Genuine Multipartite Correlations. https://arxiv.org/abs/2411.11485

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