Entanglement detection in the mixed-spin Ising–<bold><italic>X Y</italic></bold> model

Entanglement detection in the mixed-spin Ising–X Y model

Arian Zad Hamid^†,

Contour plots of the negativity as a function of the temperature and the magnetic field at fixed values of and (a) γ = 0.2J; (b) γ = 0.4J; (c) γ = 0.6J; (d) γ = 0.8J; (e) γ = J, for spins (1/2,1/2).