Chinese Physics C
Entanglement in a two-qubit Heisenberg XXZ chain with different Dzyaloshinskii-Moriya couplings and an inhomogeneous magnetic field
Meng Qin, Yanbiao Li, Zhong Bai, Shang-Jin Lin, Wei Liu
Abstract
Ground state entanglement and thermal entanglement of a two-qubit Heisenberg XXZ chain in the presence of the different Dzyaloshinski-Moriya interaction and inhomogeneous magnetic field are investigated. By the concept of concurrence, we find that the inhomogeneity of the magnetic field may make entanglement last for a long time and the critical temperature is dependent on J z and b . The entanglement can be increased by increasing the temperature in some cases. We also find that the x -component parameter D x has a higher critical temperature and more entanglement for a certain condition than the z -component parameter D z .