Tight Trade-off Between Internal, Assisted, and External Entanglement
Quantum Physics
2026-04-21 v1
Abstract
We derive a tight and saturable monogamy relation for three-qubit pure states that bounds the sum of concurrence and concurrence of assistance by the entanglement with an external qubit. The bound decreases strictly with increasing external entanglement, establishing a precise trade-off between internal and environment-induced entanglement. Equivalent formulations in terms of negativity and its convex-roof extensions follow. Our result provides a unified and quantitative constraint on entanglement distribution in open multipartite quantum systems.
Cite
@article{arxiv.2604.17867,
title = {Tight Trade-off Between Internal, Assisted, and External Entanglement},
author = {Limin Gao and Chenxiao Wang},
journal= {arXiv preprint arXiv:2604.17867},
year = {2026}
}