Pairwise Entanglement in Double-Tetrahedral Chain with Different Landé g-Factors of the Ising and Heisenberg Spins

Abstract

The pairwise entanglement is exactly examined in the spin-1/2 Ising-Heisenberg doubletetrahedral chain with different Landé g-factors of the Ising and Heisenberg spins at zero and finite temperatures. It is shown that the phenomenon present in quantum non-chiral ground states is twice as strong as in quantum chiral ground states and that it gradually diminishes with increasing temperature until it completely vanishes at a certain threshold temperature. It is also demonstrated that the strong magnetic field maintains a weak thermal entanglement quite far from the saturation field, although the ground state is non-entangled.

Ground State, Magnetization Process and Bipartite Quantum Entanglement of a Spin-1/2 Ising–Heisenberg Model on Planar Lattices of Interconnected Trigonal Bipyramids

“…To date, the bipartite entanglement has been rigorously examined in several one-(1D) and two-dimensional (2D) mixed-spin Ising-Heisenberg models formed by the identical Heisenberg dimers or triangular clusters which interact with each other via the intermediate nodal Ising spin(s) [36][37][38][39][40][41][42][43][44][45]. The investigations brought a deeper insight into the thermal and magnetic-field-driven changes of the phenomenon [36][37][38][39][40][41][42][43], the impact of the model's parameters on the phenomenon [36,[39][40][41][42][43][44][45], as well as the evolution of the phenomenon near and above second-order (continuous) phase transitions [44,45] without any artefacts arising from approximations.…”

“…To date, the bipartite entanglement has been rigorously examined in several one-(1D) and two-dimensional (2D) mixed-spin Ising-Heisenberg models formed by the identical Heisenberg dimers or triangular clusters which interact with each other via the intermediate nodal Ising spin(s) [36][37][38][39][40][41][42][43][44][45]. The investigations brought a deeper insight into the thermal and magnetic-field-driven changes of the phenomenon [36][37][38][39][40][41][42][43], the impact of the model's parameters on the phenomenon [36,[39][40][41][42][43][44][45], as well as the evolution of the phenomenon near and above second-order (continuous) phase transitions [44,45] without any artefacts arising from approximations. Despite their simplicity and the general opinion that the simpler mixed-spin Ising-Heisenberg systems involving isolated local quantum correlations are artificial models, some of the results were in a very good correspondence with ones obtained for more complex Heisenberg counterparts [40] and also with experiments [38,46,47].…”