aiqbench analysis
This research investigates the nuanced relationship between quantum nonlocality without entanglement and different metrics of state discrimination, specifically demonstrating how LOCC limitations vary depending on whether one seeks minimum-error or unambiguous discrimination outcomes. By presenting a specific family of six-product-state ensembles that behave differently under these two measures, the study offers fundamental insights into the operational definitions of separable states within quantum information theory.
Quantum nonlocality without entanglement and state discrimination measures
arXiv:2506.20560v2 Announce Type: replace Abstract: An ensemble of product states is said to exhibit "quantum nonlocality without entanglement" if the states cannot be optimally discriminated by local operations and classical communication (LOCC). We show that this property can depend on the measure of state discrimination. We present a family of ensembles, each consisting of six linearly independent, equally probable product states for which LOCC fails to achieve optimal minimum-error discrimination but succeeds in achieving optimal unambiguous discrimination.
Abstract:An ensemble of product states is said to exhibit "quantum nonlocality without entanglement" if the states cannot be optimally discriminated by local operations and classical communication (LOCC). We show that this property can depend on the measure of state discrimination. We present a family of ensembles, each consisting of six linearly independent, equally probable product states for which LOCC fails to achieve optimal minimum-error discrimination but succeeds in achieving optimal unambiguous discrimination.
arXiv:2506.20560 [quant-ph]
(or arXiv:2506.20560v2 [quant-ph] for this version)
https://doi.org/10.48550/arXiv.2506.20560 Focus to learn more arXiv-issued DOI via DataCite
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Full text under the publisher's open licence · 161 words
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