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arXiv · 2007.01700

Unsaturated bipartite entanglement of a spin-1/2 Ising-Heisenberg model on a triangulated Husimi lattice

Cesur Ekiz·Jozef Strecka
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Abstract

A bipartite entanglement between two nearest-neighbor Heisenberg spins of a spin-1/2 Ising-Heisenberg model on a triangulated Husimi lattice is quantified using a concurrence. It is shown that the concurrence equals zero in a classical ferromagnetic and a quantum disordered phase, while it becomes sizable though unsaturated in a quantum ferromagnetic phase. A thermally-assisted reentrance of the concurrence is found above a classical ferromagnetic phase, whereas a quantum ferromagnetic phase displays a striking cusp of the concurrence at a critical temperature.

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Cesur Ekiz, Jozef Strecka. 2020-07-03. Unsaturated bipartite entanglement of a spin-1/2 Ising-Heisenberg model on a triangulated Husimi lattice. https://doi.org/10.12693/aphyspola.137.592

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