Rigorous Criterion for Reentrance in the Spin-1/2 Ising-Heisenberg Model on Diamond-Like Decorated Bethe Lattices

Abstract

The ferromagnetic spin-1/2 Ising–Heisenberg model on planar lattices currently attracts a great deal of attention as it may exhibit a variety of interesting phenomena such as a quantum critical point [1, 2], peculiar spontaneous antiferromagnetic long-range order [1] or several unusual spin-liquid ground states [2]. In this work, the spin-1/2 Ising–Heisenberg model on diamond-like decorated Bethe lattices will be treated exactly with the aim to study its ground-state and finite-temperature phase diagrams.