Speaker: 郭志华教授，陕西师范大学

Inviter: 李楠副研究员

Title: Trade-oﬀ relations and nonlocal advantages of Kirkwood-Dirac nonpositivity

Language: Chinese

Time & Venue: 2025.04.25 16:30-17:30 南楼N613

Abstract: The Kirkwood-Dirac (KD) distribution is a vital framework in quantum state characterization, revealing nonclassical correlations through phase-space representations. In this work, we introduce trace-norm-based measures to assess the KD nonpositivity of quantum states and derive the corresponding trade-oﬀ relations. For bipartite systems, we establish the nonlocal advantages of KD nonpositivity based on local measurements and a set of measures. We show that any d ⊗ 2 state with nonlocal advantages of KD nonpositivity is quantum steerable, but not the vice-versa. Furthermore, we demonstrate that KD nonpositivity in Werner states provides more nonlocal advantages than quantum imaginarity and quantum coherence. These ﬁndings emerge KD nonpositivity as an independent nonclassical resource with operational relevance in quantum information protocols.