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arXiv · 2006.02738

Dynamical pairwise entanglement and two-point correlations in the three-ligand spin-star structure

Mostafa Motamedifar
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Abstract

We consider the three-ligand spin-star structure through homogeneous Heisenberg interactions (XXX-3LSSS) in the framework of dynamical pairwise entanglement. It is shown that the time evolution of the central qubit "one-particle" state (COPS) results in the generation of quantum W states at periodical time instants. On the contrary, W states cannot be generated from the time evolution of a ligand "one-particle" state (LOPS). We also investigate the dynamical behavior of two-point quantum correlations as well as the expectation values of the different spin-components for each element in the XXX-3LSSS. It is found that when a W state is generated, the same value of concurrence among all qubits arises from xx and yy two-point quantum correlations. On the opposite, zz quantum correlation between any two qubits vanishes at these time instants.

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Mostafa Motamedifar. 2020-06-04. Dynamical pairwise entanglement and two-point correlations in the three-ligand spin-star structure. https://doi.org/10.1016/j.physa.2017.04.007

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