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

TL;DR

This paper investigates bipartite entanglement in a spin-1/2 Ising-Heisenberg model on a triangulated Husimi lattice, revealing phase-dependent entanglement behavior and thermal effects on concurrence.

Contribution

It provides a detailed analysis of bipartite entanglement using concurrence in a complex lattice model, highlighting phase-specific entanglement features and thermal reentrance phenomena.

Findings

Concurrence is zero in classical ferromagnetic and quantum disordered phases.

Concurrence becomes sizable but unsaturated in quantum ferromagnetic phase.

Thermally-assisted reentrance of concurrence occurs above classical ferromagnetic phase.

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.