Activate Genuine Nonlocality From Distinguishable Sets in Tripartite Systems

ABSTRACT

A set of orthogonal quantum states in multipartite systems is of genuine nonlocality if it is locally indistinguishable in every bipartition. If it is locally reducible when the parties are separated, we say that it has genuine nonlocality of type I; otherwise, it has genuine nonlocality of type II. For a locally distinguishable set without local redundancy, if there exist some orthogonality preserving local measurements such that each outcome leads to a locally indistinguishable set, then we say that it exhibits the activation of nonlocality. We activate type‐I and type‐II genuine nonlocality of orthogonal product state sets in tripartite systems. In particular, we tackle the local irredundancy problem with partial trace operation and ‐ary numeral systems to significantly simplify the proofs. Our results also address the open question raised by Bandyopadhyay et al. [Phys. Rev. A 104 , L050201 (2021)]. Furthermore, we observe the activation of hidden genuine nonlocality in multipartite systems, which highlights the applications of nonlocality based on state discrimination in different practical scenarios.