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arXiv · 2506.18128

Dilution of Entanglement: Unveiling Quantum State Discrimination Advantages

Atanu Bhunia·Priyabrata Char·Subrata Bera·Indranil Biswas·Indrani Chattopadhyay·Debasis Sarkar
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Abstract

The states in the three-qubit GHZ SLOCC class can exhibit diverse entanglement patterns, as they may have no entanglement in any reduced subsystems, or show entanglement across one, two, or all three bipartite cuts. Significant research has explored how such states can be used in entanglement-assisted discrimination tasks. In this paper, we analyze the relationship between probability of error and amount of bipartite and multiparty entanglement, examining how different levels of entanglement impact the accuracy of state discrimination. Also we have shown that the generic class of GHZ state provide some advantages in probabilistic distinguishibility. However, perfect discrimination typically requires maximally entangled states. The use of non-maximally entangled states as a resource for perfect discrimination remains an open problem in this area of research. In this manuscript, we propose a method to explore the perfect distinguishability of orthogonal product states using non-maximally entangled states, utilizing the GHZ SLOCC class structure. Moreover, these findings offer deeper insights into the relationship between entanglement classification and nonlocality, potentially shedding light on how different entanglement structures influence nonlocal behavior in quantum systems.

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Atanu Bhunia, Priyabrata Char, Subrata Bera, Indranil Biswas, Indrani Chattopadhyay, Debasis Sarkar. 2025-06-22. Dilution of Entanglement: Unveiling Quantum State Discrimination Advantages. https://arxiv.org/abs/2506.18128

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