Thermal entanglement in the mixed three-spin X X Z Heisenberg model on a triangular cell


Han S. D. , Aydiner E.

CHINESE PHYSICS B, cilt.23, 2014 (SCI İndekslerine Giren Dergi) identifier identifier

Özet

We numerically investigate thermal entanglement of the
spins (1/2,1) and (1/2,1/2) in the three-mixed (1/2,1,1/2)
anisotropic Heisenberg XXZ spin system on a simple triangular cell
under an inhomogeneous magnetic field. We show that the external
magnetic field induces strong plateau formation in pairwise thermal
entanglement for fixed parameters of Hamiltonian in the case of the
ferromagnetic and anti-ferromagnetic interactions. We also observe
an unexpected critical point at finite temperature in the thermal
entanglement of the spins (1/2,1) for antiferromagnetic case while
the entanglement of the spins (1/2,1) for ferromagnetic case and the
entanglement of the spins (1/2,1/2) for both ferromagnetic and
antiferromagnetic cases almost decays exponentially to zero with
increasing temperature. We conclude that this critical point in
entanglement of the spins (1/2,1) for antiferromagnetic case
indicates the presence of the quantum phase transition at finite
temperature.