Two-spin and multi-spin quantum entanglement in V12 polyoxovanadate molecular nanomagnet

K. Szałowski

doi:10.1016/j.jmmm.2021.168782

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arXiv · 2110.09613

Two-spin and multi-spin quantum entanglement in V12 polyoxovanadate molecular nanomagnet

K. Szałowski

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Abstract

The paper reports a computational study of the quantum entanglement in V12 cluster molecular magnet. The low-temperature properties of the system are modelled with anisotropic quantum Heisenberg model on a tetramer of spins $S=1/2$ in the external magnetic field. The two-spin entanglement is quantified using the concurrence, whereas the fidelity serves as a measure of four-spin entanglement. The analytic and numerical results are derived and discussed, emphasizing the importance of real-space and spin-space interaction anisotropy and the role of quantum level crossings in the entanglement description in V12.

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K. Szałowski. 2021-10-18. Two-spin and multi-spin quantum entanglement in V12 polyoxovanadate molecular nanomagnet. https://doi.org/10.1016/j.jmmm.2021.168782

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