Maximal extension of converse monogamy of entanglement for tripartite pure states
Phys. Rev. A 113, 052410 – Published 5 May, 2026
DOI: https://doi.org/10.1103/y2b9-xjjm
Abstract
Unlike classical correlations, entanglement cannot be freely shared among multiple parties. This unique feature of quantum systems is known as the monogamy of entanglement. While it holds for all multipartite pure states, its converse—weak entanglement between two parties enforces strong entanglement with a third party—occurs only under specific conditions. In particular, Hayashi and Chen [Phys. Rev. A 84, 012325 (2011)] demonstrated a qualitative version of the converse monogamy of entanglement (CMoE) for tripartite pure states by employing a hierarchy of bipartite entanglement defined through the relations among various separability criteria, and Singh and Datta [IEEE Trans. Inf. Theory 69, 6564 (2023)] later extended this notion of the CMoE from the viewpoint of distillability under one-way or two-way classical communication. In this work, we extend their results to the CMoE with broader conditions, and furthermore show that our extensions are maximal with respect to the hierarchies they considered.
