Ground-State and Thermal Entanglement in Three-Spin Heisenberg-XXZ Chain with Three-Spin Interaction

<正> The entanglement properties of a three-spin X X Z Heisenberg chain with three-spin interaction are studiedby means of concurrence of pairwise entanglement.We show that ground-state pairwise entanglement,pairwise thermalentanglement,or quantum phase transition is not present in antiferromagnetic spin chain.For the ferromagnetic case,quantum phase transition takes place at △=1 for anisotropic interaction and at some values of three-spin couplingstrength,and pairwise thermal entanglement increases when the value of J/T increases and with anisotropic interactionand three-spin interaction decrease.In addition,we find that increasing the anisotropic interaction and the three-spininteraction will decrease critical temperature.