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Non-local properties of a symmetric two-qubit system

A. R. Usha Devi·M. S. Uma·R. Prabhu·Sudha
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Abstract

Non-local properties of symmetric two-qubit states are quantified in terms of a complete set of entanglement invariants. We prove that negative values of some of the invariants are signatures of quantum entanglement. This leads us to identify sufficient conditions for non-separability in terms of entanglement invariants. Non-local properties of two-qubit states extracted from (i) Dicke state (ii) state generated by one-axis twisting Hamiltonian, and (iii) one-dimensional Ising chain with nearest neighbour interaction are analyzed in terms of the invariants characterizing them.

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A. R. Usha Devi, M. S. Uma, R. Prabhu, Sudha. 2005-12-06. Non-local properties of a symmetric two-qubit system. https://doi.org/10.1088/1464-4266/7/12/042

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