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arXiv · 2111.07833

Beyond the entanglement of qubit pair in a mixed state

S. Shelly Sharma·Naresh K. Sharma
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Abstract

Given a multipartite quantum system that consists of two-level particles (qubits), one may or may not have access to all the subsystems. What can we know about the entanglement of the multiqubit system and residual correlations beyond two-tangle if we have access only to two-qubits at a time? Algebraic analysis of two-qubit states yields monogamy constraints on distribution of entanglement between sub-systems of an N-qubit state and criterion to determine if the state has multipartite entanglement. Monogamy constraints, reported in this letter, are relations between well known entanglement measures such as one-tangle, two-tangles and three-tangles of an N-qubit pure state.

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S. Shelly Sharma, Naresh K. Sharma. 2021-11-15. Beyond the entanglement of qubit pair in a mixed state. https://arxiv.org/abs/2111.07833

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