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arXiv · 1710.00139

Effect of three-spin interaction on thermal entanglement in Heisenberg XXZ model

Jing-Heng Fu·Guo-Feng Zhang
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Abstract

The effect of three-spin interaction k on thermal entanglement between alternate qubits is studied using pairwise concurrence C and energy level diagram. It is found that k breaks the symmetry about the effect of magnetic field h on C. It shifts a dip structure and gradually effaces a boot structure when |k|<|J| (J is spin exchange coupling). A peak with C maintains 1 appears and expands, elbowing the dip backwards when |k|>|J|. A sudden change of the concurrence occurs around |k|=|J|, h=-k. Similar conclusions about nearest-neighbor qubits are directly given.

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Jing-Heng Fu, Guo-Feng Zhang. 2017-09-30. Effect of three-spin interaction on thermal entanglement in Heisenberg XXZ model. https://doi.org/10.1007/s11128-017-1731-7

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