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arXiv · 2008.05138

Quantum coherence, quantum Fisher information and teleportation in the Ising-Heisenberg spin chain model of a heterotrimetallic Fe-Mn-Cu coordination polymer with magnetic impurity

Hamid Arian Zad·Moises Rojas
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Abstract

The effect of non-uniform magnetic fields on the Ising-Heisenberg chain of a heterotrimetallic coordination compound $\mathrm{Fe-Mn-Cu}$, modeling a magnetic impurity on one dimer is studied. This impurity is configured by imposing non-uniform magnetic fields on each sites of $j-$th interstitial ionic dimer $\mathrm{Mn}^{2+}-\mathrm{Cu}^{2+}$ of the chain model. The quantum coherence and pairwise entanglement between spin-1/2 magnetic $\mathrm{Mn}^{2+}-\mathrm{Cu}^{2+}$ ion dimers clearly depend on the site which the impurity is located. It is demonstrated that when the magnetic impurity is considered for one magnetic dimer, by altering Ising nodal exchange interaction and Heisenberg anisotropy parameter of the impurity dimer, the entanglement can be enhanced to the maximal value 1 at a special fixed magnetic field. Moreover, we find that the quantum Fisher information of the model with magnetic impurity behaves considerably different from the original model. Besides of the quantum resources like concurrence, we prove that the quantum Fisher information can be used as new quantum tool for estimating the quantum phase transition in the model under consideration. On the other hand, thermal teleportation can be significantly optimized by adjusting the magnetic impurity, and a strong increase in the average fidelity is observed. Finally, the magnetic impurity can be manipulated to locally control the thermal entanglement, coherence, quantum Fisher information and teleportation unlike the original model where it is done globally.

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Hamid Arian Zad, Moises Rojas. 2020-08-12. Quantum coherence, quantum Fisher information and teleportation in the Ising-Heisenberg spin chain model of a heterotrimetallic Fe-Mn-Cu coordination polymer with magnetic impurity. https://doi.org/10.1016/j.physe.2020.114455

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