Can multipartite entanglement be characterized by two-point connected correlation functions ?
Quantum Physics
2024-12-02 v4 Strongly Correlated Electrons
High Energy Physics - Theory
Mathematical Physics
math.MP
Abstract
We discuss under which conditions multipartite entanglement in mixed quantum states can be characterized only in terms of two-point connected correlation functions, as it is the case for pure states. In turn, the latter correlations are defined via a suitable combination of (disconnected) one- and two-point correlation functions. In contrast to the case of pure states, conditions to be satisfied turn out to be rather severe. However, we were able to identify some interesting cases, as when the point-independence is valid of the one-point correlations in each possible decomposition of the density matrix, or when the operators that enter in the correlations are (semi-)positive/negative defined.
Cite
@article{arxiv.2108.03605,
title = {Can multipartite entanglement be characterized by two-point connected correlation functions ?},
author = {Luca Lepori and Andrea Trombettoni and Domenico Giuliano and Johannes Kombe and Jorge Yago Malo and Andrew J. Daley and Augusto Smerzi and Maria Luisa Chiofalo},
journal= {arXiv preprint arXiv:2108.03605},
year = {2024}
}