Thermal entanglement in the Heisenberg XXZ model with Dzyaloshinskii–Moriya interaction

By the concept of negativity, we investigate the thermal entanglement in the two-spin ( 1 2 , s ) Heisenberg XXX and XXZ models in the presence of Dzyaloshinskii–Moriya ( D M ) interactions respectively. Through calculation, we know that for the XXZ model, the Δ and s can be used together to control the extent of entanglement and, in particular, to obtain large entanglement. The effect of spin in both models shows that it can increase the critical temperature and the negativity decreases as the spin increases. We found that the DM interaction has different effects on Fermi and Bose systems so it can not only excite entanglement but also affect the entanglement in different spin systems.